Thoma:
The 991 911 will make its debut at next September’s Frankfurt Motor Show, and goes on sale in the UK the following month. More powerful 911 Turbo, GT3 and GT2 models will follow in 2012.

Read more: http://www.autoexpress.co.uk/news/autoexpressnews/259060/next_porsche_911_spied.html#ixzz14TCcHnDT

 If I would get a buck for everytime a carmagazine said that a car launches at a specific date, and failed miserably, I would be a millionaire...the fact is that, unless they quote a reliable SOURCE, from within Porsche in this case, all these are simply speculations based on their intuition more than anything else. And in any case, I think Autobild or Ams are MUCH more reliable sources than some british magazine, at least in this case, simply because they are a couple miles away from porsche's headquarters. So if they haven't mentioned a release date yet it means, by all probability, that porsche hasn't mentioned a release date either.