I was thinking about switching to Rails many, many times in past. I've messed around with it and coded up some util type stuff (probably not enough) and found that it doesn't really fill some great void that's missing in Python. Of course Rails does offer a hipper, younger, more vibrant community. If you already have a strong toolset in Python why switch? I don't write nearly the amount of server side code as I used to anyway.

Also Google still supposedly uses Python.