If you're interested then go ahead. But I think you should play FF13 first.
Personal, I listened to all the fan-backlash. Last summer I gave the first FF13 a try and found it to be very enjoyable. Obviously, I tried the second game as well and it was fun, too.
The first game gave me some major FFX-vibes in regards to gameplay. I don't want to repeat myself, so just read my post here: http://www.gamefaqs.com/boards/619315-final-fantasy-xiii-2/65176834
13-2 is a little bit more different. The areas are more open, but also more limited. there are not many different places, instead you visit many areas in different time zones. And you can backtrack whenever you like.