I do not play FFXI but I am an avid fan of the FF series, having played FF1-10 and been a fan of the series since the original game came out on the NES.
I haven't been able to play because I don't have the available blocks of time to play FFXI and also I live on a college campus with crappy internet access (here it's more an interMITnet than an internet). However, I've been reading threads on various websites' FFXI forums since Jan 2003, so I've been following it since near the beginning.
I know a lot about the game's mechanics and story from having read about it and having seen screenshots. If you don't know how to react to me, a non-player, just think of it this way- I am very well informed about the game and know some things lower level players might not know (for example, I knew who the final boss of the Zilart expansion was in Jan 04, well before a good deal of players knew), but there are some things, little things I may not know.