I'll add to what Michael said - Sharpening in Photoshop is very effective. Some really nice big prints come out of small-sensor DSLR's like the Canons and Nikons. It just takes the right work in Photoshop to do it. I've had great luck following Scott Kelby's advice in his book Photoshop CS for Digital Photographers. There are several techniques, and sample settings to try. It's probably even easier and quicker to use Nik Sharpener Pro, which is a Photoshop plug-in.

In theory, the Foveon may be the way to go - but it'll be a long time before it will be a serious contender. Of course, a "long time" in digital can be a couple of weeks!