Yup. Just names of the rolling monthly updates. To see what version you are currently on go to the Sonar "Help menu > About" and the current version will be on the splashscreen that pops up. This only started happening in the past few months so if you don't see a version name you are on an older update.
The differences in each version can be found in the monthly eZines on the site (I'll go dig it up if someone doesn't beat me to it).
However the latest version will be the most up to date and have everything shoen in the eZines EXCEPT maybe some of the exclusively monthly extra content for subscribers. If you were not subscribed when the update came out then you won't have those few one off things but they won't affect the core program. Mostly FX Chains and samples/loops.