http://www.scifi.com/scifiwire/index.ph ... 0&id=37607
SCI FI Channel confirmed that it will not renew its record-breaking original series Stargate SG-1 for another season, but will pick up its spinoff series Stargate Atlantis for a fourth year. SG-1 aired its 200th episode on Aug. 18, and the SF series is the longest-running SF show on American television.
SCI FI issued the following statement on Aug. 21: "SCI FI Channel is proud to be the network that brought Stargate SG-1 to its record-breaking 10th season. Ten seasons and 215 episodes is an astounding, Guinness World Record-setting accomplishment. Stargate is a worldwide phenomenon. Having achieved so much over the course of the past 10 years, SCI FI believes that the time is right to make this season their last on the channel. SCI FI is honored to have been part of the Stargate legacy for five years, and we look forward to continuing to explore the Stargate universe with our partners at MGM through a new season of Stargate Atlantis."
Without SG-1, I don't see Atlantis lasting more than another season or two.