Well if you like JRPGs that are relatively difficult (way harder than Final Fantasy and somewhat harder than Dragon Quest) then you'll probably enjoy it. It works on a pseudo-real-time calender system, whereby any significant event (taking a school lesson, socialising, going to the dungeon and fighting enemies - yep, the usual) will move the day along by one stage, so morning to noon, noon to afternoon etc.
The game only lasts for so many days but, trust me, you have more than enough time to fit it all in - major plot events only happen on full moons (once a month) and the rest of the time is taken up by school, study, clubs, socialising and levelling up. You unlock extra abilities by socialising enough with certain people, whether they be classmates or people such as a Shopping Channel salesman or a little girl at the local shrine.
If you get to a certain level of friendship with a female character (apart from the loli at the shrine) you can date them and eventually have sex with them, though it's not shown and only (heavily) implied through dialogue. It's still heavily based within anime traditions, but nowhere near as much as the typical JRPG. In particular, a certain character called Jubei is impressively realistic and believable.
Oh, by the way. The add-on for Person 3 (known as Fes) is coming out in the US on the 22nd of April (or thereabouts) and Persona 4 is currently in development for the PS2.
How do you guys feel about the upcoming Persona 4? I'm personally looking forward to it, even though it smells a bit of a cash-in. I don't mind that kind of thing so much though, as long as they do fix some of the minor niggles I had with the game.
By the looks of things it's kinda like a reprise, and I think that's not such a bad thing, since I did enjoy the third (heh, fourth really) game a lot. I do hope that they're simultaneously working on a next-gen Persona though. Of course, they only got a PS3 licence a few months ago, so it's possible that they didn't start anything yet. Anyway.