This game is great! The best Xbox Live Arcade game!
The difficulty is just right because the easy levels are so easy to beat and get the par time, but the advanced ones are really hard to beat, and near impossible to get the par times on al of them. (the very last level (par time around 2 - 3 minutes) took me 18 minutes because I kept having to respawn)
It is very easy to learn but takes awhile to master.
Gameplay: The most fun xbox live arcade game so I give it a 9. I played a version on my friends MAC and was annoyed that you couldn't save, luckily this version ahs save points across the levels, just your time keeps on counting so dieing alot will prevent you from getting the par times. Most of the achievements are just the right difficulty, but it's really hard to get all of the secret "easter eggs" and finish the advanced levels in par time. You have to play alot of multiplayer to get the 2000 points in multiplayer one. The multiplayer is great though. Everyone has to run and get the gems spawning in an area and you can knock your opponents off the edge. It would be better if there was multiplayer not only on xbox live and mayby a "last man that hasn't fallen off the edge" mode.
Graphics: Good with mive shiny marble effects, but circular marbles and "square" worlds don't really show off any next-gen technology.
Sound: Perfect. I can never get tired of hearing the marbles roll around.
Value: The beginner and intermediate levels won't last you long and most will just give up on the extremely hard difficulty of the advanced levels. Multiplayer doesn't add much to the value. Would have been a way better value if it was only 400 points and not 800.