man guitar really? are you trying to be like every other highschool musician? play bass or play drums or somthing, theres to many guitarists in the world and not enough bassists
If you want to waste valuable time then get the PS3.
If you want to do something productive and good then get the guitar and practice it and make some songs.
Okay bro, because playing guitar without the goal of becoming a professional and making a living off of it is TOTALLY more productive than having loads of fun.
If staring at a TV screen pressing buttons on a controller is your definition of fun. Go right ahead.
You're sitting in front of a monitor typing words, surely you get some form of amusement out of it. I love videogames, and have been playing them since I was a wee lad. They provide an excellent field to boost your imagination and, believe it or not, in many cases, knowledge.
You don't just pick up a guitar, write some songs, then "see where that takes you", you have to be dedicated to it, and willing to make it a career if it takes you that far.
To the OP:
Get whichever one you believe will cause you more happiness, as that's all you can really get in life.