Quote:
I'm currently looking into buy either a Nikon D40 or a D40x. Are there any differences between the two besides megapixals and shutter speed, and of course the price?

Other than granting a base sensitivity of ISO100 as compared to ISO200, that seems to be it. Newer versions of cameras may have upgraded technology, but since the D40x came so soon after the original D40, this is probably insignificant.

Quote:
Also, I've read that the D40x doesn't accept all lenses. Is that true?

To have full function with either camera, you must use AF-S or AF-I lenses that have the focusing motors built in.

Type G & D lenses must be manually focused, but do have full metering.

Non-CPU manual lenses of course must be manually focused since they were designed without auto-focus of any kind, and in-camera metering does not work. They can only be used in manual exposure mode, so I guess it is time to dust off the old hand-held light-meter if you have any classic Nikon glass.

This was the deciding factor in choosing my D200 instead. My superb manual lenses, bought for the Nikon F3, work great and produce stunning quality. That said, the 18-135mm lens I bought for walkin' 'round, also produces very fine quality. While the difference can be seen at 100% on the monitor, I doubt anyone would notice it in a print. The other advantage is that the zoom is f-3.5-f5.6 while my prime lenses are f-1.8, f-2.0 and f-2.8,letting me shoot in very dim light.

Quote:
Any suggestions to help me decide between the two?

Well there are 40% more pixels which may or may not be significant. One can pretty much ignore a jump from 6MP to 8MP or from 8MP to 10MP. Going from 6MP to 10MP is getting a serious increase in resolution. It does mean substantial demands in terms of storage both on the card and on the hard-drive. The RAW images I shoot with the D200 weigh 16MB each, and a 4GB card fills alarmingly fast. It also means that you can crop more freely and print larger without such a high degree of enlargement. Going from 2.5FPS to 3FPS is minimal. Nice to have ISO100, but not a deal maker/breaker. Personally, I would choose the most recent camera as a matter of policy, unless some vital feature was deleted.

I agree. I would choose the most recent camera. Not because it is better just that it offers more resolution. Is there a big difference I think that is debateable but none of us buy a camera without the thought of using it for quite a while. I have the D200. Nice camera. One that most will grow with. I have seen images from point and shoot that equal mine in smaller print. I am the firm believe that you should buy what you can afford but buy looking ahead for what you need.