A Rihanna and Bruno R&B collab could totally smash the airplay charts. Rihanna's name will get it played on Urban and Bruno's name will get it played on HAC/AC. Both have crossed the other side as well (Rihanna with OG/SOS and Bruno with Nothin' On You) so it's not like those formats will avoid playing them just because of the other artist.
My problem with that is that if radio is taken from the equation, a lot of niche artists will get left out. iTunes, Rhapsody, and other digital sites are youth-driven, therefore you wouldn't see alternative artists or Urban/Urban AC artists charting on the Hot 100 just because their audiences do not use iTunes or those other digital sites very often. So, those artists would be at a disadvantage. Whichever format they use, no one would be 100% satisfied.
TOP 10
.
1. RIHANNA - S&M: 125.674 (+ 0.526)
2. CEE LO GREEN - F**k You (Forget You): 114.722 (- 1.073)
3. KATY PERRY - E.T.: 105.453 (+ 2.860)
4. JEREMIH - Down On Me f/50 Cent: 95.590 (+ 0.230) ▲
5. PINK - F**kin' Perfect (Perfect): 95.056 (- 1.269) ▼
6. LADY GAGA - Born This Way: 86.634 (- 2.033)
7. NICKI MINAJ - Moment 4 Life f/Drake: 86.040 (- 0.985)
8. BRUNO MARS - Grenade: 73.411 (- 1.831)
9. ENRIQUE IGLESIAS - Tonight f/Ludacris: 72.616 (- 1.833)
10. PITBULL - Hey Baby (Drop It To The...: 71.543 (- 1.411)
.
FILA
.
11. KATY PERRY - Firework: 66.939 (- 1.467)
12. CHRIS BROWN - Look At Me Now: 66.273 (+ 0.809)
13. USHER - More: 64.185 (- 0.713)
14. BRUNO MARS - Just The Way You Are: 61.204 (- 0.374)
15. DIDDY-DIRTY MONEY - Coming Home: 59.329 (+ 0.197)
16. KANYE WEST - All Of The Lights: 58.610 (+ 0.922)
17. BLACK EYED PEAS - Just Can't Get Enough: 55.794 (+ 2.143)
18. KE$HA - Blow: 54.772 (+ 1.174)
19. BRITNEY SPEARS - Till The World Ends: 53.333 (+ 1.328)
20. ZAC BROWN BAND - Colder Weather: 50.998 (- 0.594)
.
OUTRAS
.
THOMPSON SQUARE - Are You Gonna Kiss Me Or Not: 48.367 (- 0.691)
DARIUS RUCKER - This: 47.066 (+ 0.304)
KERI HILSON - Pretty Girl Rock: 46.772 (- 0.809)
PINK - Raise Your Glass: 45.911 (- 1.140)
MIRANDA LAMBERT - Heart Like Mine: 45.221 (+ 0.461)
ADELE - Rolling In The Deep: 44.918 (+ 1.644)
KENNY CHESNEY - Live A Little: 44.649 (+ 0.119)
JENNIFER LOPEZ f/ PITBULL - On The Floor: 44.199 (+ 1.163)
AVRIL LAVIGNE - What The Hell: 41.737 (+ 0.405)
TINIE TEMPAH - Written In The Stars f/ETurner: 41.148 (+ 0.570)
WIZ KHALIFA - Roll Up: 39.526 (+ 0.165)
THE SCRIPT - For The First Time: 39.388 (+ 0.953)
NICKI MINAJ - Did It On'em: 38.140 (+ 0.545)
DR. DRE - I Need A Doctor f/ Eminem: 35.692 (+ 0.534)
BRUNO MARS - Lazy Song: 34.223 (+ 0.859)
KEITH URBAN - Without You: 31.823 (+ 0.093)
NEW BOYZ - Back Seat f/Cataracs & Dev: 31.667 (+ 0.488)
SUGARLAND - Little Miss: 28.559 (+ 0.190)
THE BAND PERRY - You Lie: 28.427 (- 0.079)
TAYLOR SWIFT - Mean: 23.949 (+ 0.132)
JESSIE J - Price Tag f/B.O.B: 22.880 (+ 0.461)
JENNIFER HUDSON - Where You At: 21.430 (+ 0.120)
FOO FIGHTERS - Rope: 19.110 (+ 0.054)
MY CHEMICAL ROMANCE - Sing: 14.383 (+ 0.186)
MIKE POSNER F/LIL WAYNE - Bow Chicka Wow Wow: 13.923 (+ 0.562)
PITBULL - Give Me Everything f/Ne-Yo: 12.264 (+ 0.813)
JAY SEAN - Hit The Lights f/Lil Wayne: 9.266 (- 0.995)
COLBIE CAILLAT - I Do: 8.658 (+ 0.126)
BLACK KEYS - Howlin' For You: 8.039 (+ 0.039)
SELENA GOMEZ & THE SCENE - Who Says: 5.979 (+ 0.133)
STROKES - Under Cover Of Darkness: 4.167 (- 0.004)
RIHANNA - Man Down: 3.364 (+ 0.457)
PANIC AT THE DISCO - The Ballad Of Mona Lisa: 1.933 (- 0.035)
Both have crossed the other side as well (Rihanna with OG/SOS and Bruno with Nothin' On You) so it's not like those formats will avoid playing them just because of the other artist. 
