At the moment it appears Hip Hop is still happening. Even on the current Top 40 "Pop" chart, take a look at the top 5:
1-STRONGER -KANYE WEST
2-THE WAY I ARE -TIMBALAND
3-WHO KNEW -PINK
4-APOLOGIZE -TIMBALAND
5-LOVESTONED -JUSTIN TIMBERLAKE
And, consider the winning youth/young adult stations in the area, Z-100/Portland is very rhythmic/hip-hop. Along with WiLD/San Francisco, KUBE/Seattle, KIIS/Los Angeles.
Of course things can change, but, today, hip hop is top 40.