How can I upgrade the ruby interpreter without losing my gems inside my gemsets?
Use rvm upgrade
Say I want to upgrade from ruby 1.9.3 to ruby 1.9.3-p286 from within rvm and not loose my gemset environments. I would type the following command.
rvm upgrade 1.9.3 1.9.3-p286
Then you just follow the command line prompts that come up, simple as that. =D