We all played a mario game, but this is just a re-release of the old game. Don't believe the hype...
This game is an instant classic a few years back but at this time there are more and better games available to play. If you really want to expand your classics on your Wii this could be something for you, otherwise don't even bother spending the 5$. They made you spent ten times as much in the old days for this game and made nintendo big. Maybe you can spend the 5$ at some new developers who try to make new interesting creative games...
Besides the economic aspect of re-buying old games on a new hardware platform, this game sill has the old style feeling on all aspects of this old timer. The graphics are ok if you like pixels.
If not, there are more platformers out there from nintendo who are newer and more interesting than the old one.