Well, I've decided to take the plunge and upgrade my rig from my current Nvidia 9600GT. It's having trouble keeping up with the latest games, and I've been drooling over the ATI Radeon HD4870X2. This since I'm feeling a bit fed up with Nvidias antics and also because I figure if I'm gonna go for something I might as well go whole-hog.

Now, I'm primarily a Ubuntu-user and oddly enough since I'm willing to spend big moolah on a very expensive card I still only consider myself a casual gamer. Thus I would really like to know what the current state of support for ATI is under Ubuntu since this is my primary environment. Historically I remember ATI-cards being a bit tricky to get running properly, but last time I checked into this was almost two years ago and I'm assuming a lot has changed since then.

How much of a pain will it be to get running? I'm running Intrepid, and always keep it patched up with the latest updates.