According to GallifreyOne.com:

Outpost Gallifrey: Doctor Who RSS News Feed: “The Sun is reporting that in David Tennant’s final story as the Doctor, he will be accompanied by Billie Piper as Rose, Freema Agyeman as Martha and Catherine Tate as Donna. According to the tabloid, the three companions will face off against John Simm, returning as the Master.”

Here’s my say on this… If this is accurate, we may have campanion overload, yet again, the same scale as the 4th season finale… Overall, I have like the RTD era of Doctor Who… But at times it seems like he’s trying to script this awe inspiring tale over an entire season, and then fails at the last second with a Deus Ex Machina, because he couldn’t figure a better way to solve the problem… (eg. The 3rd Season finale, where ‘everyone thinks of the Doctor’ at the same moment, and restores him back to his current incarnation…)

And please *STOP* bringing Rose back. She’s been left in the other alternative universe, stop bridging the gap, and inventing new ways to bring Billie Piper back. There’s no need…

She was virtually useless in the 4th season, and I won’t go into that slight lisp she seemed to have in those episodes… Yes, it was a good hook to go WTF in the 4th season… But overall, other than in “Turn Left”, she was just nice eye candy… What did she really do in that season that was productive?

Yes, I welcome the return of “The Master”…. John Simm did an excellent job in the role, and I welcome to see what Steven Moffat can do in the Producers seat with The Master. I am only slightly less eager to see what RTD can do with the 2nd appearance of The Master. I’d like a cross between John Simms & Roger Delgado or Anthony Ainley, even Peter Pratt / Geoffrey Beevers…

I believe RTD did a fantastic job of bring the Doctor back to the Airways, but I hope that Steven Moffat can continue the legacy, and make it even stronger.