First order of business: updated trailer!
Now, to heavily
paraphrase from another site
New Super Mario Bros. Wii has proven time and time again how ambitious it is by satisifying just about every Mario lover out there, and today not only proves that in spades, it also includes something that everyone can love and use: Hint Movies!
Armed with all of the video walkthrough power it can muster, NSMBWii ups the ante by not only allowing you to watch Super Guide (novice walkthroughs if you're not doing too well on a level), but also giving you the option, with the price of Star Coins, to watch videos of more advanced tricks, some of them involving the co-op feature (for instance, there's a video of Luigi stomping on enemies and collecting coins and power-ups while Mario and the Toads help keep him afloat by letting their Yoshis slurp him up and spit him out so that he can accumulate 1-Ups by killing enemies). So fear not. Soon enough you’ll be able to play the game like a pro.
Lock your doors, close the blinds, cancel all priorities, and shoot your son while you're at it.
The Koopalings are truly back.