Love Tron? Pick this up. Not so hardcore about Tron? Rent it first.
The visual presentation of the game is very nice, or at least it is at first. A few levels into the game, though, it begins to seem bland and repetitive. This is partially because the color pallette is drab and unendingly dark, and the overly generalized landscape makes knowing where you're going and where you've been a bit confusing. I don't think I can blame the art department for this too much, as the visual look and feel of the game is very consistent with the movie tie-in source material.
I found the overall level design to be shallow and uninspired. Much of the game follows a "kill everyone in the room-navigate to another room-repeat " pattern, and I rarely had to employ any real creative thought when figuring out how to get from Point-A to Point-B. Occasionally a room can only be cleared by solving a puzzle. These garden variety puzzles generally consist of triggering one or more switches in the right order, sometimes while simultaneously fighting off hostiles.
The game's controls are a very mixed bag. In a combat oriented action game, you would expect the majority of your deaths to occur during combat. But in this game 90% of your deaths will occur when you're just trying to get from one area to another. The environments aren't the problem here -- the obstacles you have to tackle are almost always very straight forward (often to a fault, as mentioned earlier). The issue is whether or not you can get your on screen counterpart to do what you think they should. I think the problem stems from linking the "Action" button to the same button as the "Sprint" button. Most players will want to hold that button down pretty much continuously, just to get from place to place quickly. But if you accidentally bump a wall or a bench you'll go vaulting off somewhere you didn't intend. I don't know why they didn't just make sprinting an independent function of the analog stick. Fortunately, combat controls are crisp and intuitive. Plus, the attack animations are entertaining to watch. Who doesn't enjoy watching a bunch of frisbee ninjas go at it? I particularly liked that players have genuine incentive to use the block button. Some enemies would be nearly impossible to defeat without it, and good balance between offense and defense is essential in cases where you're being swarmed by a ton of different enemies types at once.
A couple levels have your character cruising around in light tanks or (briefly) on light cycles. The tank controls were a little twitchy and tough to get used to, but overall I found those levels to be the most fun in the game. The instruction manual doesn't say much about it, but the different disc powers have a very significant effect on the tanks weapons and speed. Figuring out how to exploit the best of each power while in the tank was great fun, especially on "Insane" difficulty. The light cycles, on the other hand, were a disaster. The light cycle levels are too dark and chaotic to see what you're doing very well, and the controls are too sluggish (both with the stick and with the Move controller) to respond even when you can. The multi-player light cycle experience is much better. It's a terrible shame none of that potential made it into the single-player campaign.
The developers clearly made some effort to design hostiles that have weaknesses to specific types of attacks, and so it pays for the player to do a little tactical management of the special abilities that each different disc weapon has to offer. On the other hand, once you've selected the right disc combat mostly boils down to just spamming the special attacks and then hightailing it to the recharge strip so you can spam some more. In that regard, I think this game was off to a great start but I'm left wishing the developers had spent just a little more time on the enemy design. My feelings in this manner are particularly strong where the bosses are concerned. With only a couple exceptions, the bosses amount to little more than super-foot soldiers who you have large health bars and who hurt you more when they hit you. The final "boss" was a huge disappointment.
Tron: Evolution has it's high points too. The music and sound design is great. The voice acting is good, but not great. The visual presentation overstays its welcome some, but is at least very faithful to the source material. The online experience was very enjoyable, although the player matching function seems broken. And I think it was a stroke of genius to have your experience and upgrades follow you in and out of online play. I was disappointed when my level capped out at 50--I want more! Speaking of upgrades, there are a ton of them and they get doled out at a satisfying pace so long as the player ventures out to "the grid" once in a while. There's also a number of interesting extras to find if you're a completionist. The RPG-ish aspect of this game is pretty light, but well implemented nevertheless. The recent DLC map pack is a decent addition also, and contains an excellent nostalgic nod to the first movie. Finally, the story is decent. It's not great, but it is decent. And it fills in some interesting narrative about what happened between the movies.
In my heart of hearts, I think this game is really a 6 or maybe a 6.5. But it's Tron, and despite it's faults I can't help but love and support it. The fan service in this game is quite good, and as movie tie-ins go Tron: Evolution is better than average. So my fan-boy tilt compels me to give it a 7. I think players who are less hardcore about Tron will likely appreciate this game at more face value, and give it a lower score. If you love Tron, then I recommend this game. If you don't, I think it's worth a rental trial.