While Matt Smith appears to be avoiding the Twitterverse (a bit like E-Space?), the Sixth Doc has been broadcasting tweets for a couple of days now and seems to have got the hang of it fairly quickly.
Who will be next? Can't really imagine Tom, or Peter or Sylv. Definitely not McGann or Eccles. Tennant or Matt Smith for our money.
Oh, and Frazer Hines is also tweeting, very intermittently.
A lot of people are turning up at the blog seeking an answer to this question.
The answer, as far as I know, is that he is not. Neither are any of the other Doctors to the best of my knowledge, though I'd guess Colin is the most likely of all of them to take the plunge.
Some other Doctor Who types who are on Twitter include Murray Gold, Sheridan Smith, Noel Clarke, Neil Gaiman, Jason Arnopp and Paul Cornell.
I've compile a list below of some types you might want to follow.
Doctor Who types on Twitter
• Ben Cook
Feel free to suggest any I've missed.
For a good period of the night, Twitter's trending topics were dominated by Doctor Who and Matt Smith, as The Eleventh Hour showed on BBC1.
There was a cheeky mention of Twitter by Smith too, which can't have done any harm.
Also, most likely for the first time ever, there was quite a lot of mentions of Logopolis - as the Sci-Fi channel continued its Doctor Who weekend.
Earthshock is also on - look for Adric trending later on tonight.