Rosie O'Donnell and Michelle Rounds.

Rosie O'Donnell's becoming a wife again.

The talk show host's publicist confirmed to ABCNews.com that O'Donnell is engaged to her girlfriend, Michelle Rounds.

"They are engaged, but no date has been set," O'Donnell's rep said. Us Weekly reported earlier today that the two plan to marry over Christmas and said that O'Donnell broke the news to her "Rosie Show" studio audience on Friday.

O'Donnell and Rounds, a New York City headhunter, made their public debut as a couple in September. In October, O'Donnell told " Nightline's" Cynthia McFadden that she was attracted to Rounds from the moment they met at a Starbucks this summer.

"I thought she was a 28-year-old heterosexual girl, because that's what she looked like to me. And she's a 40-year-old gay woman," O'Donnell, 49, said. "My gaydar was way off!"

"But I think if I had known that she was gay, I wouldn't have been brave enough to talk to her," she added. "She's very beautiful, it's very strange. And she's really lovely, and she's very … we laugh a lot."

O'Donnell has four children with ex-wife Kelli Carpenter, whom she married in 2004. They split in 2007.