Versus usually, but not always, refers to the debate between SW and ST. Covering such topics such as: Which franchise has faster ships? Which franchise has better technology? Which side would win in an total war scenario?
The Versus, however, is not limited to only SW vs ST, but can be applied to any matching between any science fiction franchises, from fairly balanced matches, <someone put a fair versus example here!> to outrageously unfair matches, such as Star Trek versus the Xeelee.