The basic info for the titan has been set up on the wiki please feel free to edit as you see fit. The logins aren't yet tied in with VBulletin, but if you had an old acct your login should still work for editing.
http://wiki.ppcgeeks.com/index.php?title=HTC_Titan
If this gets updated well enough we can use it as a basic resource for the general questions like custom roms, ram, ESNs etc.