SanDisk UHS-1 works in D40 camera
I bought a new 16GB SanDisk UHS-1 SDHC card to take advantage of the higher write speed for my D7000 body and it works well there but I thought I would try it out in my trusty D40, also. As to compatibility, it works like any other SD card I have tried and I do see a speed improvement when emptying the buffer to the memory card. When shooting raw in continuous mode, the buffer fills after about 4 or 5 shots and then waits until the buffer has enough room for another shot before the camera fires again. With some cards this time is over a second but with the new UHS-1 card it is much shorter of a wait time, a noticeable improvement.
I'm not suggesting that the D40 needs this new card and you should run out and buy it but if you have the card it will function correctly and deliver an improvement in write speed.