The GTX 275 looks like a very strong mid priced card with nearly the performance of the GTX 285. It should also ensure that the GTX 260 prices are driver further down.
This article also highlights some interesting tidbits about the new beta forceware drivers. The 185.65/68 drivers seem to really improve performance on the GTX 200 series cards compared to the WHQL drivers, pretty much giving the GTX 275 almost the same performance as the GTX 285 on the WHQL drivers. I'm going to give them a shot!
http://www.bit-tech.net/hardware/graphics/2009/04/03/radeon-hd-4890-vs-geforce-gtx-275/5185 driver notes:
http://forums.nvidia.com/lofiversion/index.php?t94086.html