While this is not the last season of Grey's Anatomy, it could well be the swan song for Patrick Dempsey and Ellen Pompeo, whose contracts are up at the end of the spring.

On that front, Shonda Rhimes is proceeding as if "everything's going to work out."

"I know both Patrick and Ellen are excited about the idea of continuing, but that doesn't mean everything's going to work," the executive producer tells TV Guide.

Either way, regarding Season 8, Rhimes has some good news for MerDer fans ...

"While the couple ended last season apart thanks to the rift over the clinical trial, "we open the [first] episode with Derek working on their dream house."

"I would love to have them moving in around the end of the season."

The catalyst for their reconciliation? Shonda says, "Baby Zola is transformative for Meredith, and what happens will be painful, unexpected and wonderful."

As for Cristina's unplanned pregnancy, we'll know by the end of the September 22 season premiere whether or not she keeps the baby. Think she will?

Other story lines in the works for the coming Grey's Anatomy Season 8:

• A giant sinkhole opens in a Seattle street during the two-hour premiere.
• New chief resident April will likely lose her virginity ... but to whom?
• We'll be introduced Jackson's mom, possibly played by Debbie Allen.
• The continued declining health of Alzheimer's-stricken Adele Webber.
• A Shepherd family reunion for Derek and his mother and sisters.

Thoughts on these Grey's Anatomy developments? Comment below!

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.