Apple are believed to be announcing iOS5 at WWDC in June. The (quote) “big news” is that there are revamps of widgets and the notification system. I’d personally hope you’d be able to get rid of widgets when you want to, rather than having to hide them or stash them away in a folder you never look at.
They have to announce it now, really, seeing as there’s no new hardware to tout. Apple may also announce Cloud Storage for iOS and 10.7 Lion. We may not see iOS5 until the Autumn.