Mostly compatibility ones with the Wii U version. There's also a bunch of bug fixes. For reference: (http://smilebasic.com/debug/) (you'll need to translate the page, though).
@jamdigga, you can't say that after using it for a few hours (more likely a few minutes), try to learn how to use it and then tell us what you think.
@chrysopras, is you want to learn an easy programming language then it's definitely worth it, and it's only $10.
@Szilárd
SmileBASIC is a full on programming language, which you can use to make games, tools, etc. As I said before, the possibilities are endless! You can even MAKE a game engine using it!