Facebook has apparently added AJAX to their photo galleries. A number of people (including Owen Thomas of Valleywag) have emailed me about the update. When you click through the photos in each gallery, they load practically instantly. This resembles the classic lightbox gallery style. Lightbox has always cached the previous and next photo to enable faster loading times.
Owen also pointed out that some of the photos now use the subdomain “ll” which references limelight’s caching services. This partnership isn’t actually new so my guess is that they simply added another photo server. This minor change greatly improves Facebook’s gallery feature.
Facebook appears to consistently make minor changes to their user interface to improve the user experience. I’m looking forward to the larger changes such as contact grouping and multi-language support. Who knows when those updates will take place!