I'm hoping that the 4 for Verizon works out well. AT&T is rubbish in my area. So I've waited. But now I'm not sure. Verizon is supposed to be rolling out their LTE network so I'm wondering if the iPhone 5 will be able to take advantage of that. I might just wait a couple months to see if there's any news about a 5 on Verizon this summer.
As for cases, I'm a huge fan of
Switcheasy. I have a 2G iPod Touch and have the Rebel Touch in Skeleton. It fits awesome. Covers everything on the sides and back. And comes with a couple screen covers that last a long time. When I get the iPhone I'm most likely going with a Capsule Rebel in black. These things are super durable.