I bought my first smartphone last year. It's an Asus Zenfone. It works great, despite some quirks. I felt like with the Zenfone, the smartphone was beginning to take a quantum leap forward in features. Phones are getting a bit more memory, somewhat faster CPUs, a bit better screens, and improved cameras but you would expect all of these things. In terms of new and interesting features, it seems like we're in a mature market where we've all decided upon what it means for a device to be a smartphone.
Microsoft recently Offered support of $70 Million for a start, perhaps Cyanogen will bring some excitement back. At worst, they'll come up with some new ideas that Samsung can license or copy. I don't see a whole lot to distinguish current smartphones (except that Asus does not permanently glue batteries inside of its products).