Loads of fun, but feels a bit empty for an anniversary collector's edition.
Overall, what you get here is just the same thing that was offered as a SNES cart all the way back in the SNES days, only in Wii disk form. That is both, the good and the bad news. Given the storage space used, I can't feel but disappointed that they wasted potential. They didn't even include the version of the game that includes Super Mario World, it's just the original All-Stars. Given this was a 25th anniversary edition, they could have added a bit more. The original unaltered versions of the games, for one could had been a great addition. Copies of Super Mario World and Super Mario World 2, and perhaps also Mario 64, would had turned this into a must own for anyone,not just collectors. I still have all those games in cartridge format, but would be nice to just be able to slide in a physical disk into my Wii (it just feels better than depending on the Virtual Console.)
Also included is a Super Mario History Soundtrack CD and Booklet. The booklet dedicates one page to every game with some lines on the games by Miyamoto, Tezuka and Kondo. Unfortunately it's just a one liner per game per creator and the rest of the page is dedicated to game images and screen-shots. Not bad, but I would had been happier with more notes on the games.
The soundtrack CD contains memorable themes from every game all the way through Super Mario Galaxy 2, but not that many themes per game. That may come as a bit of a disappointment to some. I also would had wish they had dedicated some room for some audio documentary, even if short, by any of the creators.
In closing: this includes loads of fun, but feels a bit empty for an anniversary collector's edition. If you want it, though, get it quick as it's likely going to start fetching high prices once stock runs out.