Ellen DeGeneres totally had the greatest birthday of all time -- at least, that's what we're gathering from her late-night announcement on Twitter. The talk show host posted a photo online tonight (Jan. 28) of a surprise she received for her birthday. What was it, exactly? Okay, it's really more a question of who than what -- Justin Bieber.

That's right, Beliebers. Get ready to see Justin hanging out with Ellen during her show tomorrow (Jan. 29). While we're not sure what, exactly, the segment will entail (whether it'll just be an interview or if there's more in store), we're totally excited. The best part of all this? Ellen was, apparently, completely surprised that Justin made the appearance. Awww!

Justin later took to Twitter to wish Ellen a happy birthday, also mentioning the visit. He said, "Good seeing u today @TheEllenShow. Happy birthday! Sorry I was so nervous," to which Ellen retweeted and responded, saying, "You were perfect. Thanks for surprising me!" SO cute.

Are you guys super excited to see what Justin has in store for Ellen? We TOTALLY are! Tune in tomorrow (Jan. 29) to check it out!

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