From the BBC
http://www.bbc.co.uk/news/entertainment-arts-13594932
It does seem funny that, having just reinvented their look, he is now putting them on ice for a while.The Daleks are to be given "a rest" from Doctor Who, writer Steven Moffat has told the Radio Times.
Moffat, who is also the BBC television show's executive producer, said: "They aren't going to make an appearance for a while. We thought it was about time to give them a rest."
The Daleks were voted the scariest villains in the history of Doctor Who in a poll of fans in 2007.
Moffat said they had been defeated by the Doctor "about 400 times".
Created by Terry Nation, the Daleks are the Doctor's hugely popular enemies who have made regular appearances in the long-running science fiction show since first appearing in 1963.
Moffat said: "There's a problem with the Daleks. They are the most famous of the Doctor's adversaries and the most frequent, which means they are the most reliably defeatable enemies in the universe."
Recent episodes of the show, which stars Matt Smith as the timelord, have been criticised for being "too scary for children".
But Moffat said: "It is horror, but horror for children. It's scary in the way that a fairy story can be scary."
Not that I object to this in any way - we've seen far too much of them since the series returned. In old Who, from Tom Baker onwards, they were used rather sparingly. Tom only faced them twice in 7 years.