Apple has just posted a new version of the iPhone OS 4.0 firmware for the iPhone and iPod touch. We're downloading it as we speak and we'll keep you informed on any novelties it might be bringing/hiding.
***Update 1
Alright, the most interesting update I can see for now is an extended time limit for app multitasking. In the beta 1, a closed app could ask for 5 extra minutes to complete its task (like the Flickr one in the keynote). Well, now you can ask iPhone OS 4.0 Beta 2 to give you as much as 10 minutes before it freezes the application.
***Update 2
Alright, so we've installed it and Apple just added a sleek new transition animation to the recent apps tab. It's a carousel with the apps being displayed on a wheel which rotates. We'll try to get some screenshots or a video a bit later.
***Update 3
Here is a video of the app switch animation (via TIPB):
