Anti-Java:
- verbose, sometimes cumbersome
- poor choice for template scripting (can be mitigated by using a secondary scripting language such as Groovy, Jython etc.)
Anti-Python:
- no particular standard framework, must research and choose (or just use standalone utility modules on top of WSGI)
- still relatively limited hosting options (other than GAE or own server)
Anti-RoR:
- no native Unicode, in a modern web scripting language? For shame
- potential performance scaling issues
Personally I ended up with Python, but all these options - as well as .NET - are easily defensible.
