I just popped a new Xerox WorkCentre 6505 out of the box, hooked it up to ethernet and turned it on. All test pages work correctly. I am able to add the printer via it's DHCP address and it prints correctly.
However, I can't get it to show up in the list of printers shown by default in the Windows 7 Add Printer window:
Should I be looking at the SMB settings on the printer?
The Add Printer dialog you are using only shows printers that have been shared by computers on the network. The Dell printer is shared from a computer with a hostname of 'SHIPSTATION'.
First of all, I'd give the new Xerox printer a static IP (or static DHCP lease), and maybe create a DNS entry for the printer to save you having to remember the IP address, then depending on the size/equipment on your network, you have a couple of options:
If the printer supports SMB (and it's enabled) then you should be able to see it listed. So, yes, look at the printer's SMB settings.
Note that Win7 will see the printer (via its IP address) on the network, whereas older versions of Windows won't even try. Even Win7 will only look in the current subnet. For anything else you need to install it as a local printer and create a Standard TCP/IP port for it.