Is Sofia Vergara back together with ex Nick Loeb?

Sofia Vergara was spotted with her ex-beau Nick Loeb on Thursday night in NYC and the pair certainly looked like they were back on! Check out these other on-again, off-again couples who have weathered the storm and gotten back together after splitting up. Also, Katy Perry surprised fans with a special treat at a screening of her flick "Katy Perry: Part of Me," in London on Thursday, and we're taking a look at some of the best celeb Twitpics of the week. Let us know on Facebook or Twitter which are your favorites — and why!

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