The 4th generation iPod touch announced by Steve Jobs today features two cameras: a rear camera, and a front-facing camera. In that way, it’s similar to the iPhone 4.

The front-facing camera is, in fact, identical to the iPhone 4′s, recording and shooting still photos at 640×480 resolution (also known as “VGA”). Notably, this is less than the device’s screen resolution, which is 640×960, but it’s still plenty good enough for its primary purpose, FaceTime.

The rear camera, however, is far different from the iPhone’s. Instead of 5 megapixels, the iPod’s camera is just short of 0.7 MP: 960×720 for stills, and 1280×720 for 720p (HD, or High Definition) videos. (Source)

While it’s far worse than the iPhone’s, it’s still better than the front camera, and its resolution is higher than that of the device’s Retina display.

The rear camera also does not have a flash, while the iPhone 4 has an LED flash (which can also be continuously lit for videos, or used as a flashlight or “torch”).

Finally, it doesn’t support HDR (High Dynamic Range imaging), which will be supported by iPhone 4 in iOS 4.1.

It’s still unclear to me whether the iPhone 3G and/or iPhone 3GS will support HDR when the software update becomes available for them. The original iPhone certainly won’t, because iOS 4 doesn’t support that device at all.