IN THE BLUE: Beyonce, Jay-Z Welcome a Girl!

It's all over but the singing: Beyonce and Jay-Z last night welcomed their much-anticipated daughter via scheduled C-section, according to various reports. Details are sketchy: E! Online reports that the baby's name is Blue Ivy Carter, while the New York Post has it as Ivy Blue Carter.

A rep for New York City's Lenox Hill Hospital tells the Post that Beyonce checked herself in early yesterday evening, and that mom and Ivy Blue (or Blue Ivy) are doing fine. The couple's reps are so far predictably mum, but congratulations were making the rounds on Twitter, with Rihanna tweeting: "Welcome to the world princess Carter! Love Aunty Rih."