Apple will be holding an event this Thursday, April 8th at 10:00am PT to show off the new 4.0 Firmware. One of the biggest features rumored to be announced is the ability to run applications in the background simultaneously.
Additionally rumored is that hitting the home button twice will bring up an Exposé like view of the apps currently running.
Instead of showing screenshots of current apps, it would show the icon of the apps. This would be one of the main features that competitor devices like Androids and the Palm Pre have. Of course, if you’re jailbroken, you can already do this with Backgrounder.