We use pip over easy_install
I'll just point out that rvm isn't a pip for ruby. It only manages what version of ruby you're currently using and allows seamless switching. It comes in handy with ruby because of all the compatibility issues between ruby versions and rails versions. Pip is a sophisticated package manager that can be used with virtualenv to isolate where Python libraries are installed. They are indeed both good tools for development but serve different purposes.
Someone commenting on their workflow using these tools would be awesome as well.
I tried to install Ruby the other day and I swear the packaging is broken 9 times out of 10.