I just stumbled across a very practical description of a Mono project that was written by a J2EE developer. He is open minded and provides good info. (Warning: this developer reports having problem with Mono and Ubuntu. I am using a more recent version of both Mono and the Mono framework, and I have experienced no such problems)
I experienced most of the problems he mentions with an earlier Mono, but the latest version is a breaze. Let me know if your milage differs.