I've got a Canon EOS 10D, 6MPixel Digital SLR
It's big, heavy and was fecking expensive but the picture quality is *awesome*.
You can see some
here.
The connection is USB 1.0 which was a bit surprising but CF cards can't even do that speed yet so it isn't a problem. I personally got a cheap 256MB CF card which is apparantly the slowest on the planet (300K / Second).
I've used it on Mac, Windows and even BeOS. It's easiest on the Mac with iPhoto but the supplied Windows software works fine. It should work on any system which supports the PTP standard (new digi-cam standard).
I don't print much but I've got a Epson stylus Photo 1290 which will print up to A3+ size. I've only printed A4 size from the camera but you can't tell it's taken with a digital camera and they're better than any normal prints I've had done, I should be able to go to A3+ without problems.
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Whatever camera you get make sure it's got a decent sized lens, it doesn't matter how many pixels you've got if they don't have a good light supply.
Only problem with hires digicams is the room the pics take up, if you take a lot as I do you need lots of room - I backed up and filled a couple of DVDs!
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