Coming in at No. 4 are Jen and Justin, who co-starred in "Wanderlust" and then lusted after each other for over a year until Mr. Theroux popped the question on his 41st bday in August. And ever since he slipped that bling on her ring finger, rampant rumors have been spreading. Did they have an engagement party? Nope! It was just a holiday party. Is she preggers? Maybe. But she may have just had one too many bites at breakfast. Will they wed in 2013? Fingers crossed.