Meat Boy is a platformer with some things that I like and some things that I hate. It's also the easiest impossible badge on Kongregate, so if you're looking for (relatively -- it's still not exactly trivial) fast points, give it a try. (I don't mean this as a criticism of either the Kongregate badge-awarding process or the game; after all, some impossible badge has to be the easiest.)
The plot, if it can be called that, is extremely simple. Dr. Fetus has kidnapped Bandaid Girl and you, Meat Boy, must rescue her. There doesn't seem to be any rhyme or reason to the weirdness of the characters, but it doesn't affect the game at all. Anyway, the game consists of pretty standard platforming action, with extensive use of wall-jumping, as you fight your way through the various levels. There are three worlds, each with 15 levels in them, but you don't have to finish all of them -- you only need to finish three levels out of every five to advance to the next set. This is nice; if you're completely annoyed by a level (and believe me, this will happen), you can just skip it and try another. (The final level is not skippable, but it's also not particularly rage-inducing.) Each level features a wide variety of you-killing machinery -- sawblades, spikes, flaming pits, you get the idea.
The controls in the game are simple, but frequently irritating, particularly since the game's collision detection is very unforgiving and will zap you if even a pixel of yours comes into contact with something unpleasant. It's especially difficult to accurately control your character in midair; I must have died a thousand deaths by jumping and flying over the space I was trying to jump to into a wall of fire, or a bottomless pit, or something else unpleasant. However, each given level is quite short, so it doesn't feel too oppressive to have to try repeatedly in order to actually pass the level. Some (but not all) of the levels feature band-aids, which can be collected to unlock various secrets (which are just cute little addons, nothing affecting gameplay). Getting these band-aids can often be an exercise in persistence, since they tend to require pixel-perfect jumping.
The graphics are in the low-res, slightly pixelated style that seems to be the fashion these days (although not to quite the extent seen in, say, Dino Run). In my opinion, at least, it's kind of ugly -- it doesn't quite work here in the same way that it does in other games. (Really, this might just be because the main characters are kind of ugly -- the rest of the graphics are fine.) The sound effects are pretty minimal. The background music gets points for at least being different for the three different worlds -- it's pretty catchy at first, but it repeats on too short a loop, and so it gets kind of irritating eventually, alas.
Overall, Meat Boy is a game which is fun and enjoyable at times and annoying and frustrating at other times. It's quick, so even though it takes a while to actually finish the game, you'll never feel hopelessly stuck or anything, and there is a nice feeling of achievement from getting that impossible badge. Still, in the end, I'm not quite sure whether I'd recommend the game or not. Give it a try, I guess -- it won't take you long to decide whether you like it or not, I'm sure.