I have an alias set up for the command
so I type "version" in terminal and get
lsb_release -dc && echo "Desktop: $DESKTOP_SESSION" && uname -a
which gives much more information to me about everything.
Description: Ubuntu 10.04.4 LTS
Linux Lucid 2.6.35-32-generic #68~lucid1-Ubuntu SMP Wed Mar 28 17:09:33 UTC 2012 i686 GNU/Linux
System monitor never shows the point versions of the ubuntu OS, just the base, eg, in my case, 10.04 (Lucid), but as you can see I am running 10.04.4.