Besides, Ruby powers many highly visible websites and web apps. If I'd be losing a sale because I develop in Ruby and NOT Python, chances are I don't want that sale in the first place.
Business continuity.
If the choice is between Ruby and Python and Clojure and any of the "esoteric" languages as far as enterprises are concerned, that's a red herring.
Google is a compelling argument, no doubt, but if the biz dudes are open to switching from a "traditional" language/framework such as Java/J2EE or .Net, there are other "established" players that use Ruby.
Please don't take this as defending Ruby, the best tool for the job should win out. If the team proposing Python is well-versed in Python, that's what they should go with. But saying that Python is a better bet than Ruby, because Google embraces it is a bit of a strawman.
Obscure languages are a form of vendor lock-in, in that sense.
if you're developing SAAS or something, then I'm sure you're right, but that argument doesn't apply to everybody.