I think it all depends on the type of lovin' you're going for. My roommates and I were very...um...practical, to put it in a PC way, when it came to issues of looooooove, so our picks last year were:
Rufus Wainwright - Instant Pleasure
-and, the greatest lovin' (not love

) song ever written-
Tenacious D - F*@$ Her Gently
I mean, anything that goes, "What's your favorite posish? That's cool with me, it's not my favorite but I'll do it for you," is too stellar to adequately put into words.
And...call me crazy...but the latest song that gets me pumped up and ready to go is "She Hates Me" by Puddle of Mudd. Maybe it's just because it always puts me in a good mood.