Hey Upper East Siders, subbing in for Gossip Girl here -- your usual source for scoop on the scandalous lives of Manhattan's elite. Spotted: Boys and girls making out with each other all over the city. But who's smooching who? Click through this slideshow for the ultimate insider's guide on which lips have had the most action.Wednesday, May, 14, 2008, 10:14 PM

It's a thin line between Chuck and Nate and no one knows that better than Blair Waldorf. The perfectly coifed and dressed Queen Bee of the most popular clique of girls at Constance Billard, B is the epitome of Upper East Side royalty. But alas, all is not well in her kingdom. Trouble started when her boyfriend N slept with Serena and things only got worse when N couldn't get over her. Heart-broken from losing N and coming in second (again) to S, B let loose at C's burlesque club, which culminated in the most scandalous Upper East Side hook-up since S and N's raunchy romp -- B losing her virginity to C in the back of his limo. Skip forward a couple of days and B's back with N and they finally seal the deal. Two guys in one week -- that's how the Queen rolls.Wednesday, May, 14, 2008, 10:14 PM

With his chiseled good looks and boy-next-door charm, could you really blame Blair, Serena, Jenny, and Vanessa for having locked lips with Nate Archibald? Coupled with B since kindergarten, it would seem that the pair was destined to live happily ever after, but N soon tired of his doting girlfriend and had a passionate one night stand with her best friend (at a hotel bar, no less). Even though B forgave him for his steamy night of indiscretion, N wasn't quite over S yet and mistakenly smooched a masked J at the masquerade ball thinking she was S. It seems that N was torn between the brunette and the blonde… oh the choices! What's a guy to do? Hook up with a new girl of course! N stomped over to Brooklyn and instantly won the affections of V with his mad SAT writing skills. But after their late-night kiss, I'm sure his writing wasn't the only thing that impressed V. Can the Upper East Side's Golden Boy have a relationship with a girl from the wrong side of the river? Or does his heart belong to the high society gals? And if so, which one?Wednesday, May, 14, 2008, 10:14 PM

He's Chuck Bass. Need I say more? A self-proclaimed playboy, it's no surprise that C has swapped spit with Georgina, Jenny, Serena and Blair. Since losing his virginity to G in 6th grade (no details please!), C will latch onto anything in his field of vision. He's the Patron Saint of all that is sleazy and arrogant. C took a stab at seducing a guilt-ridden S after her surprise return to New York, but was quickly shoved away. Then his failed attempt to date-rape freshman J at the Kiss on the Lips party earned him a shiny black eye. A couple of rejections can't keep a bad boy down, but can a broken heart? After getting hot and heavy with B in the back of a limo, C began to have genuine feelings for her… butterflies even. C and B's secretive tryst was short-lived when B quickly abandoned him the minute N came beckoning. Can the so-called ladies man's broken heart be mended? Will sparks fly again for C and B?Wednesday, May, 14, 2008, 10:14 PM

She's the girl every guy wants… and every girl wants to be. Serena van der Woodsen has the uncanny ability to steal the spotlight without even trying and that's probably why she's been spotted smooching Nate, Chuck and Dan. Now that S is back in the city, she's determined to become a better person. Before S shipped herself off to boarding school in Connecticut, she drunkenly slept with her best friend's boyfriend N -- S at her bad girl finest. After returning from her abrupt disappearance, C tried to have sex with her and she promptly denied his advances AND his truffle oil grilled cheese sandwich -- S at her most reformed. And what better way to completely turn over a new leaf than to date Brooklyn-bred D, a Mr. Nice Guy through and through? All should be swell for S and D, but what fun would that be? Now that Georgina has returned she's been stirring things up a bit -- okay, a lot. Is Georgina threatening to destroy S's relationship with D, along with S's recent streak of good behavior? If I were S, I'd think about releasing my otherwise dormant dark side on G, because the only way to destroy a psycho is to play dirty.Wednesday, May, 14, 2008, 10:14 PM

From the looks of it, Lonely Boy is anything but. Dan Humphrey may be lacking money, status and entitlement, but that hasn't stopped him from kissing Serena, Georgina and Vanessa. When your best friend is as beautiful, intelligent and sassy as V, it's only a matter of time before your friendship becomes something more. But in this case, absence didn't make a heart grow fonder as D forgot all about V once she moved away and he received an open invitation to date the leggy blonde he'd been lusting over since he spotted her at a birthday party in 9th grade. Now that he's got the girl, the question is: Can he keep her? Is S's upper crust baggage too much for D to handle? Apparently so because he's already gone to first base with G. All bets are off, but does D know that he's playing with a wildcard?Wednesday, May, 14, 2008, 10:14 PM

Jenny Humphrey is the downtown girl trying to break into the uptown circle, but I think her social-climbing is putting a damper on her love life. The trio of smooches she received from Chuck, Nate and Asher were the result of mistaken identity, an attempt at date-rape, and a gay cover-up, respectively. Poor Little J, that's the price you pay for wanting to be on top.Wednesday, May, 14, 2008, 10:14 PM

Vanessa Abrams has been Dan's BFF since they were six years old. V moved away to Vermont and returned to confess her love for him, but soon realized that she'd been elbowed out of his affections by his new socialite girlfriend Serena. V doesn't really understand the world of these UES kids and has remained somewhat of an outcast… until she fell for the brooding charm of Nate Archibald. Finally, V got her shot at romance, but everyone knows that dating an Archibald is a tortured process, especially because he never really got over S. But V of all people should know how it feels to fall for someone who's in love with S.Wednesday, May, 14, 2008, 10:14 PM

When even Chuck Bass keeps his distance, you know it's bad… and I'm being kind when I call Georgina Sparks bad. Swiping C's v-card is minor league for G, and she's done with child's play. As though blackmailing Serena wasn't enough, G has got her evil claws in Dan and she's already pounced. Beware, Georgie's on the prowl and it's not about what she's going to do, it's about who she'll be doing it with.Wednesday, May, 14, 2008, 10:14 PM