Hi Mark, did you try disabling the firewall? Based on my experience this is usually the cause.
I think another possibility is that the computer is connected to the 5 GHz band and the printer most likely uses 2.4 GHz.
I have disabled the firewall and the printer is of course hard wired to the network. All the other machines I have both wired and wireless can print to it fine. For some reason this Centrino wireless just won't talk to it. If you ping the gateway, a loopback, or another machine on the network it is fine. But if you try to ping the printer or go to it's internal web configuration page you can't reach it. It is the weirdest thing I have ever seen.
I'll try the band change tonight to see if that makes any difference.