If the press release specifically stated that the game is Super Mario All-Stars, I don't think this compilation includes Super Mario World. That game was titled Super Mario All-Stars + Super Mario World, so the article probably would have mentioned Super Mario World.
Ever since New Super Mario Brothers Wii launched, I've thought it'd be neat if they created a New Super Mario All-Stars that included all the previous Mario games in the NSMB style. The co-op alone would make it worthwhile. Too bad that isn't what this is.
It's a shame it's just a port. It'd be neat if it included options for NES, SNES and Wii graphics. It'd be awesome if it included an option to use the NSMBWii engine for multi-player. Imagine playing Super Mario Bros. 2 USA with four players. But then, we're looking at a $50 release instead of a $30 release, I'm sure.
There are fan projects for New Super Mario Brothers Wii out there that have already re-created the entirety of the original Super Mario Brothers, as well as a lot of Super Mario World. I believe someone is working on SMB3 as well, though I'm not sure. They are worth checking out if you are interested. Super Mario USA is not possible, of course, since it's a whole different type of game.