How fortunate it got an AI of 84 then, meaning it was as well received with the wider pubic as episodes like Amy's Choice, The Girl in the Fire Place and Dalek. Typically DW episodes will get over 85, but 84 hardly indicates a massive level of dislike from the audience.

And even then, there have been some episodes as badly or worse received by fandom, like Fear Her and Love & Monsters and somehow this hasn't lead to a collapse in ratings either.

Ratings will vary from week to week. This week may be up a tad, down a tad or roughly the same. If they are down a tad chances are it;s more to do with the earlier start time than anything else.

What is "AI" in this context? I get that it's some sort of audience appreciation measure after the fact but beyond that...?

Appreciation index. You can read all about it here:

http://en.wikipedia.org/wiki/Appreciation_Index

An AI over 85 is considered excellent, with over 90 being exceptional.

http://en.wikipedia.org/wiki/Appreciation_Index

I agree with people's arguments with regards to differing viewing habits but surely this argument is applicable for any BBC show to incorporate iplayer and BBC 3. I'm thinking of EE which has come under scrutiny (all fair in terms of quality) but isn't perhaps revered in the same vein as Dr Who.

the difference is that Doctor Who timeshifts proportionately much more greatly than most other shows. It's really leading the television viewing revolution and really has done from the start.

Eastenders is currently way down on what it used to get in final ratings, as opposed to Doctor Who which remains the same.

eta: heres an example of how the soaps were rating in 2005, for example

http://www.digitalspy.co.uk/media/ne...y-ratings.html

over 13 million for Eastenders, over 12 million for Corrie....just on overnights. Takes an extra special event to get close to those sort of figures now!

Thanks DemonDan and Muttley!