Rihanna - Rude Boy
I know it was a big hit and that she needed a hit from Rated R, but it just doesn't fit at all. I always skip it.
Other songs which are really bad, but don't really ruin the album for me:
Lady Gaga - Fashion. Bleh.
Ke$ha - Dirty Love. I know Iggy Pop is a legend, but this song doesn't work at all.
Pretty Hurts, Blow, Blue, Heaven, Jealous - Beyonce
Complicated - Loud
If this were the movies or whatever, I can't remember the name - Teenage Dream
Roc Me Out - TTT
Well in that case, the Tinie Tempah edit of Hanging On ruins Halcyon.
Here to China ruins 18 Months
Hot ruins The Best Damn Thing
I've Tried Everything ruins In Case You Didn't Know