I kind of agree with OvrClkr and notty22. The GTS 250 doesn't really need extra cooling. Now, if anyone needs a better GPU cooler, it's my GTX 470! LOL
Even so, a 10C drop in idle temp is pretty good! Although I too wondered about VRAM temps just judging by the heatsink in the photo. Running GPU-Z should clear up the question about temperatures though.
Run Furmark a few minutes with GPU-Z open and see how hot things get.