I read a review today of a book called 'Retromania' which, according to the reviewer, essentially argued that pop music in the 2000s had lost its forward momentum and more than any other decade was obsessed with the past.
A few observations about this:
1) Every musical era is backward-looking to some degree. (I think the author would agree with this.)
2) Having said that, I think a case can be made that the 2000s have been more backward-looking than previous decades. It is possible this may in part be associated with the massive increase in access to pop's history through digital libraries.
3) Doing it first is not necessarily doing it better.
Is pop's time of innovation over and we are now doomed to an endless recycling of past tunes? Maybe, but you never know where the next wave of innovation will come from. A book I once read suggested that the next mega innovative pop star will come from outside the US and probably from one of the less developed nations. That was over ten years ago and we're still waiting, but hey don't count it out yet.