Yea theres some teething issues with the 5000 series drivers but seems even Nvidia slipped up recently with it's fan killer driver the other week. I've been using the 10.3 beta driver for about a week since getting my 5870 and to be honest the drivers are pretty stable here, so the whql one due next week should be okay.
One thing that amazed me personally was that my new card uses around the same amount of leccy as my old 8800 it replaced and a heap less than the 260's. I was seriously looking at a 285/295 card since christmas until I saw the stupid money they were asking for them still. Then I decided to wait 3 more months for a 470GTX but it's just become a running joke now that it uses way more leccy than a Ati equivalent and it's bearly much faster (not to mention about £100 more as I only paid £235 for mine), and the final insult that put me into ATi camp was the fact that Nvidia seriously screwed everyone around on the specs... down from 512 core to 448 WTF! I'd only consider Nvidia again with the next generation of FERMI in a year or two if they actually keep their promises and specs dont go down while the costs go up.