@Roman references some good articles that looks at the pros and cons of ASP.NET Identity and the membership provider model.
ASP.NET Identity gets away from the membership provider model, which I believe is a good thing. There are some definite problems with Simple Membership when you wanted more advanced security features and if it was anything more than "simple" you ended up creating your own security solution. I am moving forward with ASP.NET Identity because it much more extensible than Simple Membership and although the documentation and support is weak right now I believe it will get better as it matures, just like Simple Membership did. If you can get past the growing pains I believe ASP.NET Identity will be a far better solution than Simple Membership was and I like the tight integration with OWIN
, which will be important going forward. As for email verification with ASP.NET Identity, here is an article that describes how to implement this. You can get complete source code here. And the solution described here also provides password reset with ASP.NET Identity.