I picked it up yesterday it's pretty good, probably wouldn't recommend it if you've never played guitar, or if your very good (been playing for years etc). But for someone like me who can play chords, couple of songs, power chords and knows the basics (but still shit), it's a pretty good tool for teaching and refining techniques, plus you get to learn a few classics on the way.
I wouldn't say its a game, it's more of a training/ practicing tool, I'd say you have to want to learn guitar, and stick with it. It's not pick up and play like guitar hero (and not something that can be picked up in a few hours).