Some info was posted about Idina’s appearance on Glee on Watch with Kristin’s spoiler chat at E! Online:

Saranoh2009: Any scoop on Will/Emma on Glee?
Idina Menzel is back, as you might know, and it looks like it’s gonna be a nice, long visit! Idina herself just told our Marc Malkin that she’ll be in “at least eight episodes,” and that is more than enough time to find her way back to her ex make-out buddy, Will Shuester. Menzel was pretty mum on plot details, but she did say, “The only thing I can say is my character becomes definitely more multi-dimensional,” the hot mom says. “She definitely has a big heart so we’ll see new aspects to her personality.” Meanwhile, Dianna Agron tells me she’s hoping Idina’s return means a reunion with the baby she gave up to her, Beth.

1987Dav: Hey Kristin! Anything on Rachel, Shelby and Quinn?
Rachel’s mom Shelby (played by Menzel), will definitely be doing a duet with her daughter. “I just came from the studio recording,” she says. “I won’t say what it is, but it’s something with Lea (Michele) and it’s one of the best songs ever written.” One of the best songs ever written? We guess it’s Eddie Murphy‘s legendary ditty “Party All the Time,” but that’s just our opinion. And clearly, it’s right.

One of the best songs ever written??? I can’t wait to find out what it is! Any guesses?