Breaking news... the latest issue of Doctor Who Magazine, number 409 (officially released later this week) apparently confirms that David Tennant will be appearing in the third series of The Sarah Jane Adventures, according to various online fans who have received their subscription copies of the magazine early.
More on this story as and when it breaks.
For now, settle down and watch this charming clip from John Barrowman's Tonight's the Night - featuring Barrowman and Tennant on board the TARDIS set!
6PM UPDATE - Den of Geek! are running the story, with extracts from DWM itself:
Also joining the Tenth Doctor is the robotic mutt, K9 but RTD is keen to stress that this is no fleeting appearance by David Tennant. The writer says, "... it's more than just a cameo from the Tenth Doctor! He's a proper part of the story." He also adds that the two-parter is "extraordinary, wild and powerfully moving," cryptically adding, "let's just say that the wedding of Sarah Jane will be a day for everyone to remember!"
The 2 part adventure is written by Gareth Roberts.
A while ago I heard that Roberts would be contributing a story called "The Impossible Sarah Jane Smith" for the third series. Is there any truth to the rumours - and just who is Sarah Jane marrying?!