Provided porting an app to a new platform isn't too arduous then it could work out. Games especially, they are typically very easily ported since most run atop game engines that are very easily recompiled.
That said, I think Apple will eclipse HP with iPad2 and they have the 'cool' brand recognition. Think HP and you think printers still. Blackberry on the other hand...
Let's wait for the battery spec to really see how this thing will work out. Apple cut many many corners to give the ipad fabulous battery life and the video I have seen of the touchpad makes it look really slow, very unsnappy performance. Possibly they are running developer builds and it will be faster when it ships.