Our counterparts at TMZ have learned Britney Spears will indeed be leaving rehab this week, and sources say the troubled pop princess has made one of the most "amazing" turnarounds in celebrity memory.

Sources say Britney Spears and her soon-to-be official ex, Kevin Federline, had an "amazing meeting" on Sunday. They are not only getting along, they are hammering out the terms of custody.

We're told when Britney Spears gets out, she and Kevin have agreed to a 50/50 split with custody of their two children, Sean Preston, 17 months, and Jayden James, 5 months.

The plan is for Britney to eventually gain primary custody and Kevin will have visitation. No word on whether Brit and Jason Filyaw are engaged.

Jamie Lynn Spears, Britney's sister, and Britney's mom, Lynne Spears, have been at Kevin's house helping with the kids while Britney has been getting her own kind of help in rehab.

And that help is reportedly working. We're told she has literally turned her life around. What do you think? Is our girl Cue Ball gonna make it?