Is it still too early to officially declare the age of plastic strumming/banging games over yet? 

At this time last year, GH, RB, etc dominated a lot of sales chart and mindshare.  This year?  Not a single one showed up on top 10 NPD (granted who knows about NPD top 20).  DJ hero was proclaimed fairly widely as a failure (relative to expectations), etc.

After the insane amount of milking (here's looking at you Activision), I wouldn't be surprised.

Haha was definitely short lived. Almost as short as Tony Hawk games.

I doubt its over but definitely not going to see Guitar Hero III or World Tour like sales out of them anymore. But hey they did it to themselves. Can't release the same game over and over again with little to no changes and do it 3-4 times within the year. It's obsessive and it saturates the property. Not even a Madden or FIFA game more than once a year. But when you don't change anything this is kinda what happens.

But I doubt EA or Activision will just let it fizzle out. They'll keep up with attempts to push out their plastic accessories and new ideas and maybe they'll strike gold again.

definalty wont be as big as it was in 2007-08 but with new ideas like DJ Hero and more to come, its a genre that hopefully wont go away anytime soon

All we get is retail numbers. For all we know at this point most of the revenue for music games are coming from DLC. So to say it is dying or not is way premature because we do not have enough information. It is dying for retailers? That is a question that we may soon be able to answer.

If it is over: HOORAY!!

I just didn't understand why somebody would need more than one of those games. It boggled my mind.

I don't think they'll see the sales of Guitar Hero: World Tour or Guitar Hero 3 since Activision over saturated the market without really making drastic changes to the genre, but I don't think the genre will die anytime soon.

I would hope so... but I still think they are going to be successful, just not as much as 2007-2008.

It is probably on the downward slope.

I hope Guitar Hero dies, to teach Activision a lesson.

I deserves to drop. That genre's been milked so much its lost its appeal. And those band sets was pretty pricey, almost as much as a console.