If you've looked at UTStarcom's site there are actually 2 models of the HTC Titan. They are the PPC6800 and the XV6800. I'm not sure who designed what part.
So they are the same phone except with a different case. The Mogul is the PPC flavor and has a round 5 way pad with different shaped (I think bigger..) buttons.
Verizon has the XV6800 sold as the XV6800. Bell in Canada is the only other carrier I know to have the XV flavor.
Meanwhile, the PPC6800 is sold as the Mogul (all gray, sprint) and with gray and black on Alltel (which I think looks good.) And gray on Qwest not to mention a few others. Oh and the P400 is one of HTC's names which Telus uses which I believe is a PPC flavor.
As far as software goes I'm pretty sure the phones all identify themselves as the the TITA100.
http://www.utstar.com/pcd/view_phone...&bID=76&sAct=0
http://www.utstar.com/pcd/view_phone...&bID=89&sAct=0
The sad thing is that the is little indication that the devices are made by HTC or even UTStar except for the battery and sometimes the battery cover.
But in a nutshell they are the same.