Base the decision on the software you are going to run. If it runs on the iPad, you're all set. Definitely get the 3G version, though. No subscription required from AT&T, so you can turn it on (and pay) only when you need it.
If you need more than will run on an iPad, or you need a camera, keyboard, whatever, you need to look elsewhere. Typical netbooks or the MacBook Air aren't much heavier and provide a lot more functionality. Only you can decide if you need it.
If you've got some geek in your blood, using an iPad as a client to control your home computer via LogMeIn or VNC can provide the ability to run any software you've got there, Mac, Windows, Linux, you name it.
As for iPad 2, I suspect that will be out around April. (One year upgrade cycle, like the iPhone.) Like any other tech, the one available soon is going to be better and cheaper than the one available now.