The only thing that I miss on 2.7 is psyco. I support a somewhat popular python app in the open source world, and write a lot of python at the day job, and I usually deploy an executable with bundled python interpreter, and 2.6, because psyco does not work on 2.7, and makes a HUGE difference on 2.6
pypy doesn't support gevent/eventlet, as far as I know. :(
Not yet, indeed. But according to their site they do have a stackless version: "PyPy can be configured to run in stackless mode, providing micro-threads for massive concurrency". This sounds promising, and could be used to implement gevent.