The current version of the app is essentially an Objective-C shell with a Web browser inside. When it comes to speed, this is like putting the engine of a Smart Car in the body of a Ferrari.
Applications that are predominantly HTML5 render most of the components of an app as a Web page, pulling images and content from the Web directly into the application. Objective-C takes the opposite approach, taking full advantage of the hardware in the iPhone and then building most of the functionality directly into the application so it has to collect less information from the Web.
Great news, though a slam against Facebook’s hope for HTML5 as a platform for web apps, which I hate. They’re slow and rely far too much on what are often, at best, shaky mobile connections. 21,000 one-star ratings on the App Store certainly makes a statement as well.
Bilton had a chance to use Facebook’s new native iOS app and says it’s “blazing fast,” but not a major redesign. So it’s a Snow Leopard release, but one that will hopefully lead to revisions of those one-stars.