I just finished the game myself and most of what Brad said is spot on. Compared to meatboy, ms Splosion man does take forever to start running, wall jumping is harder to pull off, and the physics are crazy when platforming on horizontal moving platforms. Whats worse is you still have to wait to recharge your jumps after landing which makes no sense to me. He was right about the spruced up graphics getting in the way of the gameplay too. One level in a tight space there was a pink Ms Splosion man, Pink explosions, a pink barrel, a pink laser, and some pink barrels and lasers blurred out in the back ground. It took me multiple times to get past that part just because i couldn't tell where Ms Splosion Man is. I fell victim to to the foreground objects and dramatic camera angle changes myself a bit too.
I think the levels themselves are great though, and while it could be better, Ms Splosion Man's controls aren't game breaking by any means. It definitely has its dose of trial and error, but I don't think the check pointing is near as bad as brad suggests and to make the checkpoints more frequent would break much of the don't stop for nothing level design that Twisted Pixel designed for this game.
As a sequel to Splosion Man, Ms Splosion Man is a great follow up, but with Super Meat Boy in town it really needed to polish some more stuff up if it wants to be recognized as a 5/5 or 4/5 type of game. 3/5 is still pretty decent and isn't meant to discourage people who want to buy the game from buying it. At worst its more of a recommendation to the people on the fence that this game isn't anything special and that they can skip it if they want.