Last week, Nina Collins was professing a love for four-figure handbags. This week, she might feel like treating herself to another new Mulberry, as big changes are underway at the Collins McCormick Literary Agency. The agency, cofounded with New Yorker editor turned agent David McCormick in 2002, is officially disbanding, but Collins will be staying behind in the downtown office (so spiffy interior designer Roy Leone includes it in his portfolio) and continue to work as Collins Literary. Flying solo is old hat for Collins, who described the split in an email as “amicable and for the best”; she ran her own business scouting foreign and film rights for ten years before teaming up with McCormick.