all the star wars movies are flash gordon type titles. they are "cheesy" titles that recall 1950s sci-fi titles. people just dont think the OT movies are cheesy because theyve been around so long and were all used to them. The Empire Strikes Back is a perfect example. Its totally cheesy.
To prove the point, imagine terminator 2:judgement day, was titled terminator 2:the skynet strikes back! it would be totally cheesy. That is how GL titles all his movies. The Phantom Menace recalls a bit of Phantom of the Opera, and other old sci-fie menace movies. Attack of the Clones is meant to recall movies such as Attack of the 50 foot woman from the early 60s.
Episode III will have an equally campy title. It will likely start with the letter R and probably include "Sith" in the Title. In my opinion, Revenge of the Sith is a good contrast for Return of the Jedi, and aptly describes the events that occur in Episode III.