There exists a discussion about Rocksmith over whether it is a game or a piece of music learning software. In my opinion, it sits in some awkward middle ground where it can't really be considered either.
The style is undeniably game-like. For those of us who spent much of their teen years playing Guitar Hero and its ilk, Rocksmith is very recognisable - you choose the least objectionable option from a selection of songs, notes scroll down a screen towards you, there's a simulated crowd and background 'band' noise, you hit notes to earn points and progress... But it's missing a lot of the key elements that makes Guitar Hero such a fun game.
Mostly, it's the showmanship that's missing. For one, you never actually see the band; there are sounds from them, so you know they exist, but the scenes where you'd see the vocalist screaming into the mike or yourself in pre-chosen pixelated form spinning around whilst playing the guitar are completely missing. It's just endless gazing out into the crowd whilst notes on the on-screen fret keep on coming. And I get that Ubisoft couldn't really include the star power concept - the idea being you create the music yourself - but they could have included the 'fret engulfed by flames' for special occasions, like getting an however-many note streak.
Whether because of this lack of showmanship or for some other reason, Rocksmith lacks the group/social activity quality that Guitar Hero has. I'll bring Guitar Hero out at parties, my friends and I will have fun hitting away at the plastic guitar knowing that it is just a game. I've played Rocksmith as a multiplayer, it's no fun (and not just because I keep on having to reassign the controller to trick the system into thinking I have two...) It feels too serious to play as a group activity.
And yet, Rocksmith wants to be a game. Indeed, it positively yearns to be played as a game, you have to practically force the mechanics to not whisk you along at an alarming pace so you can beat all of the levels and be finished with it by dinner time. There will be a occasion where you accidentally press 'Continue journey' and find you're being introduced to some new technique before you've properly understood the last one. Possibly several occasions. Because you have to wrangle it before you can properly use it as a piece of learning software, I'm not sure it can be properly identified as such.
In case you think I'm being harsh and critical here, I'm not. Not really. Ok, I wish there was a bit more 'pizzazz' with Rocksmith, but that's really a very minor niggle. Mostly, I think it's amazing. It has taught me to play something on a guitar, a feat that two professional music instructors and several friends who play guitar failed to accomplish. I'm just not sure where it sits in the current market. Maybe it's creating its own market?