My theory about concerning the changeover from DT to MS is:-

Doctor 10 does not regenerate at the end of the Christmas specials. Instead he goes off with River Song and marries her.

We then see Doctor 11 for the 1st time in episode 1 of the new series where he picks up Amy Pond.

At some point in the 1st few episodes he runs into River Song. At the end of the story River Song gets the message about going to the Library and the Doctor gives her his old Sonic Screwdriver and sends her on her way.

As for the change in the Tardis maybe it was River song that got him to redecorate (we all know how women are not satisfied unless the other halves are constantly redecorating).

I like.

I hope so. It would clear everything up.

As I've said before both Matt Smith and Ben Cook have given the 11th Doctors age as 950.

As the 10th Doctor's age was always given as around 900 I do feel that we will find that 50 years have past either between/during the Specials or between Eps 4.18 and 5.1.

If the latter it also leaves a gap to be used if there is any truth to the Doctor Who film rumour.

And explains why River thought the Doctor looked so young.

I must say I like this idea. No regeneration, move series 5 on 50 years or more. Good idea, lets hope.

I heard there would be no regeneration (apparently all to do with continuity with the proposed movie) but, as I was told that the new companion's name was definitely going to be "Susan", I'm taking it with a very large pinch of salt...

Told by who?

LOL, Karen Gillan looks nothing like Carole Ann Ford, who played Susan Foreman, who was supposed to have never regenerated!