I will keep this review to the multiplayer mode. For this alone it is worth you buying this game! Play in the same room as a friend adn you only need one copy of the game thanks to download play. But have two copies and you can play against each other anywhere around the world! I ahvent player two player tetris since i used to play my friend when i was about 7 with my big fat chunky old grey gameboy playing over a link up cable sitting a metre away from each other! So it was great to see the same basic concept was there (clear lines, more you clear, the more lines are "sent" to your opponent and fills their screen). however this version has introduced something great.... items. You can now send each other items as well that are unlocked by clearing question mark boxes. These items are similar ones to what are found in all other mario games like mario kart, which include bananas (to mix the players bricks around), ghost (so they cant see what bricks coming) and mushrooms (so their bricks come down really fast), stars (so you get all 1x4 blocks) and shells (that wil clear lines off the bottom of your screen for you). This really mixes the game up and can affect the game a lotif you use your items at the right time! The one major thing that is annoying is that if your playing against one other person over wifi then you cant play with item on, instead this mode is only available if you are paying 3 other people.
There are other multiplayer modeslike one where you share the screen and you have to build on each others blocks and push the other players blocks up their screen but the original multiplayer option is still the best one!
The single player mode of this game is also quite fun with other things on offer like missions etc. but it really is the multiplayer where this game comes alive. Two words to you.... Buy it!