You'll know whether it's worth it to you.

User Rating: 8.2 | Guitar Hero Encore: Rocks the 80s PS2
In my opinion, this is a great track list, and it's focus on the 80s theme means less filler because it doesn't try to encompass as many decades or music genres as GH I and II. As has been mentioned, there are no gameplay updates this time, but when it all boils down, Guitar Hero is really about the songs. Veteran players will know whether the prospect of 30 new songs is worth shelling out money for or not. If you enjoy the game as much as I do, new songs, regardless of the package, will entertain for months on end, long after finishing the career modes.

Sure, we're all looking forward to GH III (and more importantly, Rock Band), but in the meantime we have the option to diversify our play lists a little.