I use an HP Laser 1320NW which is wireless and has ethernet and USB, but agreed that the Apple Extreme or Express with a USB printer may be the best way to go. That way, when you replace your printer, you don't have to jettison the networking component.
I think too, you get the big advantage that you are almost completely unfettered in picking the best printer, vs. settling for TCO or other problems associated with the one that has a WiFi adapter in it.
The Kodak all-in-one printers are pure JUNK. Do not be fooled by the promise of low cost ink cartridges. There is a paper jam problem that Kodak won't own up to that plagues these things all the time. Stay away from Kodak!