Include tornado framework in consideration if you are starting out. I just love it - lightweight yet powerful. I just love how helpful Ben Darnell and folks who are maintaining the framework.
The latest YC fav kid, hipmunk.com is built using tornado.
Seconded. Its as minimal as web.py to get started but has all the templating, realtime events, and more waiting when you need them. Docs are great and sample code is shipped with it so you know it works.
The latest YC fav kid, hipmunk.com is built using tornado.