If you already have the iPad, given our time with the new iteration, we suggest giving the iPad 2 a miss. Sure it's faster, but that's speed you may or may not really need (given how fast the original iPad already is anyhow). If you don't have an iPad, and want to get Apple's shiny new tablet, then by all means, feel free to fork out the cash for it.
Original iPad users should definitely wait for the iPad 3, which should offer a significant reason to upgrade; but if you must have the iPad 2, then well, it's your cash and we can't stop you either. Rumours that the iPad 3 may make an appearance this year remain just that, rumours. So until otherwise we hear a credible source of information, expect to see a new model around the same time next year.
If you've never been an Apple user, but are willing to try it out, the iPad 2 is a great entry point. Otherwise you'll probably be avoiding this device like the plague, just like any other Apple product. That said, other tablets like the BlackBerry Playbook and HP TouchPad with their other own operating systems are coming soon, so holding off to see what they offer before you commit is probably a good idea if you're sitting on the fence.