I know we've not got series 4 out the way but i feel the momentum is building for this doctors exit and it's got me thinking about the 3 specials.

I think RTD wants to give this doctor a big build up with an amazing send off along the lines of Tom Bakers departure, 3 different stories with one link I.E, master, daleks etc.

I just have this feeling that Astrid will return to thank him for letting her see the stars by warning him of his impending demise, whether it's done with kylie or a long distance shot alluding to her we would have to wait and see.

Anyway this is my pure speculation, bordering on fanwink.

Maybe, but she's no Giles!

Maybe he's just created the ultimate Dues Ex Machina (note...I'm using it....shut up! )
Any time the Doctor faces an impossible, certain death situation, here comes a sparkly blue light to wish it all away...

Thank you Astrid for making that Cyberman spaceship dissapear, you're part TARDIS after all...see you next time I need you! *end credits*

How sad is it that I had exactly the same thought

I have just watched all DT's video diaries and at the end it does seem like DT is certainly thinking about leaving but he is also loving being a part of it.