If you're new to DSLR cameras, or digital compact cameras, it's worth keeping some sage words advice in mind: megapixels aren't everything.
While we can tell you all about why, including sensor types, image processing and lenses, it's satisfying to hear it coming from the mouths of camera vendors themselves. In this case, one Akira Watanabe from Olympus, who has come out with the claim that 12 megapixels should be enough for most people.
We've spoken to Canon about this at length in the past, and were again reminded of this at the launch of their new IXUS range. Like Sony and others, Canon isn't exactly relegating megapixels to the dustbin, but they're much keener to push things like intelligent auto scene detection, HD movie capabilities, and style (the IXUS 100 IS is only 18.4mm wide).
It's something worth keeping mind, especially if you're stepping up to an entry level DSLR.
Also see Digital SLRS - 11 models tested and reviewed