XIII-2 is almost better than XIII in every way. I suppose the character and story are a little better in XIII but there is more fun to be had in XIII-2. The characters interact more with each other and environment in this game and you can even choosewhat to say at times in the tradition of a BioWare game. The story is insane, but I think the pacing is a lot better due to the game's design. Instead of being forced through the storyline, you pick up details bit by bit. I actually like Serah's character and think her point of view is interesting. I do feel like Noel is Serah's babysitter sometimes though but it's funny. The battle system and crystarium are greatly improved. The monster recruiting idea sounds lame, but plays a lot better than it sounds and adds a layer of customization. There is now something called wound damage which causes damages to your MAXIMUM HP and must be reversed by using a wound potion. Everything else has been fine tuned and works better such as elemental attacks and buffing, and therefore makes XIII more strategic. The crystarium seems simplified at first, but it actually just got rid of the tedium of traveling along the crystarium lines when spending CP and provides more choice (you get a choice of different upgrades when you reach a new crystarium level. Do you want to unlock the medic role or increase the ATB guage of your character? How about increasing the amount of accessories your character can wear?). Also the crystarium isn't locked so leveling up different roles is more important, it is no longer a case of leveling all paradigm roles equally to stay viable. The graphics are also improved just because the zones are now HUGE and DETAILED. Some of the environments are jaw dropping. FFXIII graphics + fully fleshed out fantasy zones = heaven.

If you want to play it safe, just wait until the end of the year when it will likely be half the price it is now. Kingdoms of Amalur: Reckoning is coming out soon to keep you busy and Mass Effect 3 is coming out in about 6 weeks.