http://www.gateworld.net/news/2006/12/exclusive_third_istargatei_serie.shtmlNo concept for the show has yet been revealed.
The third TV series is also not likely to be rushed into production for a 2007 premiere in order to replace SG-1, which takes its final bow with 10 new episodes this spring. Instead, a premiere in 2008 or later is more likely at this point. (Note that, at this time in the fall of 2003, Stargate Atlantis was well into casting, script-writing, and set-building to make a July premiere date.)