# as root using 1.9.2
root@buildup:~# rvm list

rvm rubies

   ruby-1.8.7-p334 [ i386 ]
=> ruby-1.9.2-p180 [ i386 ]

root@buildup:~# which ruby
/usr/local/rvm/rubies/ruby-1.9.2-p180/bin/ruby

# as bradland using 1.8.7
root@buildup:~# rvm list

rvm rubies

=> ruby-1.8.7-p334 [ i386 ]
   ruby-1.9.2-p180 [ i386 ]

root@buildup:~# which ruby
/usr/local/rvm/rubies/ruby-1.8.7-p334/bin/ruby