According to this Yahoo Article
link full gate screening is on its way back. This article coupled with information from some contacts here at MSP indicate that this screening will be for all flights and all passengers. In otherwords your bag and person will be searched for a second time completely. There will be no randomness in this process and the flights will not be allowed to leave until every person has been screened. Their current estimates are that it will take approximately 2 hour for a two person team to screen a flight of 100 people.
My contacts indicate this is most likely the precurser to an absolute ban on all carry on luggage.
Gee I am glad I am not flying tomorrow.