Rocks the 80s comes really close to being something special but tragically falls short.
The soundtrack is good, but is lacking some really big 80s names. For example, we get a forgotten Extreme song as the last track when the 80s was the setting of the speed metal craze (Megadeth or Metallica anyone?). It almost seems that Harmonix simply chose songs that were cheap and quick to get licensed rather than looking for genuine classics. There are several artists that are strangely missing from the setlist (Motley Crue, Bon Jovi, Def Leppard, AC DC, Billy Idol, and Van Halen) but the setlist that is present has several high points and overall is pretty strong. My favs are Holy Diver, Hold On Loosely, 18 and Life, Seventeen, and I Ran (So Far Away).
The presentation of the game is almost identical to GH2 with the only exceptions being new clothes for your characters, slightly altered venues and a nice 80s sheen on the menus. Other than that it's the exact same game. Also, there are no bonus songs. I know that it would have been hard to include bonus songs from current underground acts on an 80s game but paying $50 for 30 songs is a bit hard to swallow. Sometimes the content doesn't have to match it simply needs to be there.
GH still plays great and if you can pick it up for cheap used somewhere and you can view it as an expansion pack to GH2 you will love it. However casual fans are going to want to skip this one.