[calpaterson]

In my mind, there are two main differences. First bottle supports Python 3. Second, Flask is built on Werkzeug, which is a very flexible WSGI toolkit. In practice, I have never used Werkzeug much, except for the excellect stacktrace pages, which let you run the debugger right where you problem failed. I pick bottle for new projects, basically because of the Python 3 support. Fixing unicode is worth quite a lot to me.

[schleppy_oc]

FYI, it looks like plans for porting werkzeug / flask to Python 3 may be close at hand. https://twitter.com/mitsuhiko/status/323177177367601152

[the_mitsuhiko]

Yes. Stuff is happening soon, getting prepared for it :)