This printer is the biggest pain in the arse. I've done about three or four jobs for customers with this exact same problem. Sometimes you get lucky with the various troubleshooting tips people have presented here and other times you have to format the drive and reinstall the OS.
I can't believe the amount of complaints I've heard exactly like this. But, to reiterate, here are the steps you take.
1) Try the EPSON USB setting.
2) Try the Rendezvous setting.
3) Delete the Epson printer prefs in your user library prefs folder.
4) Create a new user and see if you can print with the new user. If not, go to step 5. If you can, transfer your data from the old user to the new user. You will have to reset your prefs - iApps, other programs.
5) Reinstall OS X using Archive & Install with the "Preserve Users and Network Settings" option, customize the install and make sure all additional print drivers are installed.
6) Backup all your data, format the drive, and install. Customize the install and use all additional print drivers. You will have to reset all of your prefs - Network Settings, iApps, etc.
If none of that works, take it to an Apple Store or a Reseller and see if they can determine a hardware issue or something I'm forgetting.
