I think the clear winner is the GTX275... in some of those reviews the baby GTX260 216 beats the 4890..... still its close in other tests.
Great review, thanks! oh and I love how you always include the older gen cards (8800GTX, 9800GT) which are in many gamers computers still. This way I can gauge how my 8800GTX performs compared to the new breed... from what I can see the GTX285 is a good upgrade, delivering around 80% better performance than the old 8800GTX!
Btw, can you explain why Race Driver: GRID is more stressful on the GPU than Crysis Warhead? It sure runs faster!
I actually played some GRID today (before your review went live) and I noticed they have updated the game to include "in-game advertising" .... saw a few Aussie related ads

Also I noticed the Game was taking a lot more video memory than before.
I run at 1680x1050 with 16x AA and 16x AF + maximum details... the 8800GTX handles this ok with it never dipping below 40fps. However, memory usage used to be around 680 to 700mb... today I noticed the memory usage at 801mb! But did not see any performance slowdown... hmm.
Any chance of SLI / CF followup? The only thing I miss from your reviews is SLI/CF tests, I know you guys are not fond of these setups because of micro stutter, but they are such nice setups to have!
I heard the 4890 in CF beats the GTX295

!!!
Yapa