What have WP8 ever done for us?

I'm a mac at heat, but I try to stay informed. Lately I've been readily impressed with MS' creations, specifically with the path they seem to take with Windows 8, and WP.

However, I've failed to see why or how WP8 is such a big update compared to WP7, so maybe some decent objective human being could help me out here? As far as I can tell, the biggest update is the tiny tile, as well as support for a new type of chip. Would anyone like to elaborate?