Great game, but for newcomers, you might want something else.
This is an amazing game, a classic game, it has over 20 characters, all classic characters from the arcade. The X-box live for this game is amazing, it can be slow at some times, if the other person has a horrible connection, but that is to be expected from any other game as well, otherwise the multiplayer is a great addition to such a great game, very addictive if you are good, especially the multiplayer, it is also fun to plug in a second controller and destroy a friend on the same 360.
Bottom line: A great game, but if you're new you might want to think of purchasing something else, unless of course you enjoy losing badly on the easiest difficulty. =)