Tami, all of the escorted cruises get named and the non escorted with 10 (I think!) or more LCTers can be named as well.
We have contests to name the cruise and the winner gets a virtual tea pot. Here is an example of entering names for a contest

Here is the list of acronyms for 2010

And to answer your question, this cruise is acually FUN2, and we didn't have a contest to name it as our buddy Ralph suggested FUN2.
It was named after another big LCT cruise, the original FUN. This is so confusing but FUN2 started out on the Navigator but when the bargain for the Mariner was announced, we all jumped ship to the Mariner.
I think FUN originally stood for Fun Upon the Navigator or something like that.