I fail to see why "my ISP doesn't give me Ruby" --> "Ruby isn't mainstream".

To my downvoter, here's a list of "mainstream" providers, at the Godaddy-level, and language support:

Dreamhost: RoR, PHP, Perl, Python [1]

Godaddy @ $8/month: PHP, Perl, Python, RoR [2]

a2Hosting @ $3/month: PHP, Perl, Ruby, Python

That seems pretty mainstream to me.

[1] http://beta.dreamhost.com/web-hosting/ [2] http://www.godaddy.com/hosting/web-hosting.aspx [3] http://www.a2hosting.com/services/web-hosting/