In case you didn’t know, Stargate SG-1 has been “cancelled”.
To be specific the Sci-Fi channel in America has decided not to pay for another series after series 10. But all is not lost. According to Wikipedia they will be making two straight-to-DVD movies by the end of the year (filming in April and June). The first will wrap up the Ori storyline and the other will be unrelated (check Wikipedia for some spoilers).
Also another completely separate Stargate series is planned to start in 2008/