1. Man Repeller 
The hot things in fashion tend to burn out quickly, but Man Repeller shows no signs of giving up its status as the “It” blog. The love it receives has helped founder Leandra Medine snag design collaborations with brands including Dannijo and Gryphon.
2. Lady Gaga 
The pop icon’s outrageous fashion sense (meat dress , anyone?) has revitalized the music video and introduced the avant-garde to a new generation. With style collaborator Nicola Formichetti and her Haus of Gaga  team, the fame monster has trained her fans to expect the unexpected.
3. Derek Lam 
One of the most innovative digital efforts of the year came from Derek Lam, which, during New York’s spring/summer Fashion Week, put 16 different dresses on eBay and asked fans to vote online for their favorites. The result was Derek Lam + eBay , the “first-ever crowdsourced collection,” which featured five dresses that were sold on the auction site.
4. Anna Wintour 
Meryl Streep nailed it in The Devil Wears Prada—Wintour isn’t just imperious; she’s seductive. Fear alone wouldn’t keep Vogue the world’s most renowned fashion magazine, or make Wintour herself the icon and industry leader that she is. Of course, her eye for detail, encyclopedic knowledge of the industry, and brilliant understanding of the zeitgeist help too.
5. Shopkick 
Countless apps offer discounts and deals at retailers nationwide, but Shopkick sets itself apart with major partnerships (Macy’s, Target) and a genius innovation: Special sensors installed at participating outlets alert users to promotions the second they enter the stores.
6. Michelle Obama 
The first lady’s anointment as a fashion icon was to be expected. Less so her sense of fun: She mixes fashion-forward designer pieces with sensible separates, and keeps up with the fashion pack. It’s hard to imagine any other first lady wearing almost the same Alexander McQueen dress to a state dinner that Mila Kunis wore to the SAG Awards.
7. Heidi Klum 
Despite a rocky move to Lifetime last year, the super model-turned-businesswoman’s groundbreaking show, Project Runway, is going strong in its ninth season. And thanks to her lines of jewelry, fragrance, and athletic apparel, Klum earned the No. 2 spot on Forbes’ list of the World’s Top-Earning Models . Oh, and—damn her—she’s drop-dead gorgeous.
8. Jim Moore , creative director, and Madeline Weeks , fashion director, GQ
GQ, the fashion destination for guys who won’t admit to being into fashion, consistently demonstrates its power—and its impeccable nose for talent—with its photo shoots, which always seem to feature actors, singers, and others who are just on the verge of hitting it big. Its Best New Menswear Designer Award , most recently given to Alexander Wang, remains a coveted honor.
9. Diane von Furstenberg 
The first designer to truly embrace new media (OK, it might have something to do with her husband’s digital chops), Furstenberg moved at warp speed into e-commerce and more. She’s also a hit on Twitter , sharing advice, personal updates—and even photos of a skiing-induced black eye.
10. Andre Saraiva 
A nightlife impresario and fashion industry fixture who recently got himself appointed creative director for L’Officiel Hommes, Saraiva does a little bit of everything: nightclubs, hotels, collaborations with major brands. His latest New York club , Le Baron, opens this fall.
11. Jil Sander 
Though she’s hardly the first designer to collaborate with a big-box store, Jil Sander’s minimalist, modern collection for Uniqlo—Japan’s leading clothing retailer—was the first to show it’s possible to produce eclectic pieces for a major chain that are applauded by critics and coveted by consumers.
12. Gainsbury & Whiting, London 
The cutting-edge event production company works with a long list of high-end designers, but is best known for its outstanding collaborations with the late Alexander McQueen, including a hologram of Kate Moss on the runway . It also helped stage “Savage Beauty,” the designer’s recent record-breaking exhibit at the Metropolitan Museum of Art in New York.
13. Scott Schuman 
The father of the street-style blog, Schuman founded The Sartorialist in 2005 to showcase uniquely dressed individuals worldwide. The concept wasn’t new—Bill Cunningham has been doing it for decades at The New York Times—but when Schuman put it online, he created an offline culture in which people don outrageous dress in hopes of catching his eye.
14. Todd Waterbury 
Last year, Todd Waterbury left his co-executive creative director’s post  at Wieden + Kennedy in New York to start his own consultancy—and quickly picked up Uniqlo, for which he’s working as head creative for North America. His mission for the chain: to launch, this fall, two more stores in New York, one of which will be its global flagship.
15. Nowness 
The digital magazine, backed by French luxury goods conglomerate LVMH, is so well edited that readers don’t mind (or even notice) the parent company’s stealth advertising. Its often esoteric articles, short films, and photo spreads are a subtle exercise in lifestyle branding, successfully blurring the line between editorial content and luxury marketing.
16. Tumblr 
Despite a recent Fashion Week brouhaha, the site is undeniably influential. A kaleidoscopic spin through street styles, imagery, and advice, it captures the rogue energy of real-world fashion, and has attracted magazines and brands, which use the digital scrapbook as an informal alternative to their official sites.
17. Selena Gomez 
Gomez’s Dream Out Loud juniors apparel collection  is maximally cute and minimally risqué—which means mothers fork over the dough when their daughters squeal loud enough. The line epitomizes the celebrity-mass retailer fashion craze, including its success: Kmart estimated earlier this year that sales of Gomez’s line could top $100 million by the end of 2011.
18. Style.com 
Consistently ranked in the top five most-visited fashion sites, Style.com has the best runway pictures around, and accompanying text that doesn’t read dumb (no small accomplishment), plus news and event photos. No wonder readers range from top editors to high schoolers just learning the right Prada dress can give you a head rush.
19. Opening Ceremony 
Yes, the small chain store is “trendy” and “cool” in ways some find pretentious, but let’s give the retailer its due: It packs in a beautifully curated selection of up-and-coming designers, select established brands, a private label, and collaborations with authentically hip celebs like Chloe Sevigny and Spike Jonze.
20. Indie magazines
Underground print magazines like Dossier, Love, and Fantastic Man, bolstered by eclectic online presences, have become must reads for fashion’s elite. They shun a restrained ethos in favor of taboos like nudity and bondage, and regularly feature plus-size women and older models. With their rough, raw, and oftentimes startlingly beautiful imagery, they’re not your mother’s fashion publications.
21. Kate Middleton 
The fashion world, whether it likes it or not, is having “a Kate moment” (demure tailoring, long sleeves, scoop necks). Looking elegant even in jeans, the Duchess of Cambridge, much like Michelle Obama, expertly mixes high and low, and is good for sales: Items she wears from affordable U.K. designers like Reiss and Issa sell out instantly.
22. Stylebook 
The success of this app has brought to light a hidden obsession of many a clotheshorse: the need to index one’s closet and drawers. It allows fashion lovers—not us, really—to photograph and catalog their clothes as well as pair them with images from the Web to plan different looks, create mini mood boards, and experiment with styles.
23. A Continuous Lean 
It started out small (a list of American-made fashion brands) and ended up an arbiter of style—and a seal of approval for marketers. Founder Michael Williams has been catapulted to stardom among a (mostly male) hipster elite, but he’ll say he’s more concerned with traditional Americana than setting trends.
24. Gilt Groupe 
Gilt hasn’t done much in the four years since it launched; it’s only changed the way we shop. With covetable brands and a seamless user experience, it’s set a new standard for flash sale sites. Lately it’s branched out into retail/content hybrid sites like the menswear-focused Park & Bond, and Gilt Taste, overseen by big-name foodie Ruth Reichl .
25. Stefano Tonchi 
The man who gave identity and form to the once-unfocused New York Times T: Style Magazine is now reinvigorating W, bringing in buzz—and ad pages. The polished Florentine has injected the magazine and its website with both general interest articles worth reading and an insider-y, gossipy vibe to help create what he calls “fashion’s after-party.”
Photography by Joshua Scott