The return of the series was originally anticipated in the UK for the August Bank Holiday weekend, based upon the pattern of preview screenings of Let's Kill Hitler at the BFI and Edinburgh last year; this date had also been suggested by a number of US media outlets, though it seems that these reports were picked up through fan enthusiasm rather than official sources, especially with BBC America having already announced their series of four Doctor Who documentary specials over the August weekends. Also, when asked at the Asylum of the Daleks screening last week lead writer Steven Moffat would only indicate that the show will return "soon".
With the the 25th August ruled out, focus turned to the 1st September. BBC America have devoted an entire day to Doctor Who, showing the entirety of last year's series plus The Doctor, The Widow and The Wardrobe - the latter's scheduling of two hours (8-10pm) suggested that perhaps there was a missing programme to show at 9pm. The date was also reinforced by iTunes listing the series as being available from 1st September. However, early morning viewers were treated to a trailer on BBC America earlier this week which specifically mentioned an on air date of the 8th September - however, the channel has now reverted to trailers saying the series is coming soon. It is unsure whether the trailer was a mistake or if BBC America jumped the gun on an announcement.
Meanwhile, in the UK the new edition of listings magazine Radio Times announces that "Doctor Who is back!", with the next issue (1-7 Sep) promising a free Dalek wallchart, plus interviews with Matt Smith, Karen Gillan and Steven Moffat - the latter also providing an episode guide to the new series. However, the magazine has in recent months carried a number of front-covers/coverage of new shows that aren't necessarily in the week of publication so it isn't clear-cut that Doctor Who will premiere in the UK on the 1st September, and the show is currently absent from the BBC Media Pack for that week, implying the series may have a later debut.
The situation is likely to be clarified later this week. Schedules in the UK for the week beginning 1st September will be finalised in the next couple of days, and the press pack for the week beginning 8th September is released on Thursday.
As soon as the date is confirmed it will be reported by Doctor Who News.