I made the jump from PHP to Python a few years ago and am very glad I did. As far as frameworks are concerned, I started with Django, web.py and cherry.py and landed on on Tornado.  I love the include what you need, non-kitchen sink aspect of Python development and have found my apps to have much smaller CPU and memory footprints.  In addition, I believe Python development has made me a better developer in general.<p>I can honestly say I'd be surprised if you didn't thank yourself for jumping over to Python. Just make sure to give yourself the time and resources required for the shift in process and thinking.