Received FF13 today, for a paltry 25 bucks brand new! Played it for about 3 hours, and as advertised it is very linear so far. But, that is the case with all Final Fantasies. The battle system is probably the SWEETEST thing I've ever played on an RPG. It's very immersive, as you link skills and attacks together from you and your teammates. At anytime you can break into the chain and introduce a new "Paradigm" which will set the characteristics of what your supporting characters do. There are your standard "all-out attack", "all-out defense", "use magic", ones that set job classes to each character accordingly.
The real beauty of it is how you can go in and fully customize your own battle strategies. One of the most in depth and immersive things I've ever seen in an RPG. Steep learning curve however, but once you get it it can be a ton of fun. Story and visuals are epic of course. This is the first time I'm playing a final fantasy anywhere close to the release day, so I have no clue what is going to happen. The older ones I usually watched someone else play before I got a chance to go onto it myself. Very fun.
For any of you RPG fans out there, so far its looking like a must play just on the battle system and graphics alone. If the world starts opening up and I can start scripting how I want the story to go, than this could be the best one I've ever played.