Hip-Hop, the replacement term for Rap?

I was listening to some music today that was categorized as "Billboard's Top 100 Hip-Hop R-B Charts as of 2007/02/10". As could be assessed from the name, this is HIP-HOP and R&B music. I am listening to each track to see if I like it or not, and if I do, I add it to my MP3 player.

Some song names are as follows...there are more (like 50 total, I think) but you get the gist:

Rock Yo Hips - Crime Mob ft. Lil Scrappy
Can't Forget About You - Nas ft. Chrisette Michele
Smack That - Akon ft. Eminem
Get Me Bodied - Beyonce
Grew Up A Screw Up - Ludacris ft. Young Jeezy
06 Rap Up - Skillz
What You Are - Lionel Richie

Okay, so I'm sure everyone has heard "Smack That" and we could probably say that fits in the Hip-Hop category. Also, "What Your Are" by Lionel Richie is a sure thing for R&B although I'd call it maybe Pop as well.

But look at the names on "Rock Yo Hips" and "Grew Up A Screw Up." I don't think Nas, Ludacris or Young Jeezy were originally wanting to be known as Hip-Hop artists. In fact some other songs are sung by Trick Daddy, Chamillionaire, Lil Jon and The Game. Aren't these supposed to be rappers or some form of a rapper?

So, I'm assuming that Hip-Hop is the new name for Rap because I know they don't want to be under the R&B category.