I just picked up ME2 and im really enjoying it, so much i bought ME1 to play at lunch times at work on PC, so im currently playing them simultaneously even tho i know what happens in one thanks to the interactive comic.
but my advice BE QUICK if your going to get it on PS3, some of the free DLC expires if you dont get it before the 23rd and then you will have to pay for it if you want it, its only a few guns not any missions, but hay its free for the next 5 days!
Also dont buy it second hand the game comes with a code to claim all the DLC for free its a 650meg download, if you get it second hand youll have to pay the project $10 fee to get it!
Ive never been a fan of Western RPG's but this game has changed my mind and im only 10 hours in, highly recommend!
P.S. I payed £25, well worth it.
EDIT: my bad it actually expired last month, so 1 Gun and 1 Piece of armour is now not included in the free DLC, but still best not to buy it second hand.