I'm in the same boat. I still use my 2011 MBP for development work, and I will continue to use it until it falls apart, but I don't think I'm going to buy a new Macbook to replace it.

I love that I can open this one up and upgrade the hell out of it. It's got a better SSD than Apple ever sold for it, and more memory than Apple claims is possible. I doubt a processor upgrade is possible, but if it was, I'd be in the market for one.