I know this is a bit late in the conversation, but I think:

Rock is dying

The 90's will be remembered for grunge and teen pop, but the millennium will be remembered for hip-hop and RnB. It dominates the airwaves so much that it has even found its way into rock. Rap/Rock fusion is a direct response to the fact that hip-hop is taking over. Rock needs that fusion to survive.

As I see it, all musical "decades" never begin when they say they do. The 80's began sometime around like 82 or so and lasted until the last hair band shaved their heads; at like 1992. The 90's really started in like 92 or whenever grunge began to surface. And the 00's began in like 98 or so, when rock totally lost its directon and hip-hop's catchy hooks just snagged the entire american audience.