Agreed. I go to startup meetups and it's crazy how similar all the ideas are. My startup is B2B and ad-supported, two things that are definitely not trendy, and I kinda dig that.
I've observed this too at a number of startup pitch events. There are countless people ready to build a business based on some little missing feature of Pinterest, Twitter, Facebook, etc., but there is almost no one that wants to solve any problems in any established industry. Seems crazy to me. Sure maybe building B2B software isn't always sexy, but there are tons of interesting problems to solve, and lots of real money to be made.