CURRENT STATUS: After Stargate: Revolution spent more than two years in limbo, Brad Wright announced on April 17, 2011, that MGM would not be producing this or any other Stargate movies in the near future. Although a script was written and at one point production looked to be ready to move forward, Stargate: Revolution will not be produced.
Below you will find everything stated publicly about the film, starting with the earliest information.
NEWS & SPOILERS
"But you know what? They have a good time when they come, and I think these guys had a good time making Continuum. Is it likely we'll ever get them all again? That's kind of unlikely just because of the math. But our core folks – I will move heaven and earth to get them if I can.
"I think Jack and Daniel and Carter and Teal'c – and Mitchell now, to a certain extent, and Landry now, to a certain extent – are part of the fabric of SG-1. Fans will get mad at me if I don't put them in." (Writer and executive producer Brad Wright, in an April 2008 interview with GateWorld)
"... I thought Claudia [Black] was terrific in Continuum, but Vala won't be returning in the third movie."
"... The DVDs came out of a desire to prove we could make movies. I think we surprised the studio with what we could do on a small budget, but not enough to let us make a big Stargate feature." (Writer and executive producer Brad Wright, in a January 2009 Q&A with fans at Joseph Mallozzi's blog)
"... I had a story idea that really worked with O'Neill. And it's not just his character, by any means. It's a Stargate story that brings O'Neill back in a big way." (Writer and executive producer Brad Wright, on stage at Creation Entertainment's April 2009 Vancouver Stargate convention)
"... We were very successful with the first two SG-1 movies. Since then, the economics have changed a little bit. DVDs aren't selling the same way they were when we released those even just a year, and a year and a half ago.
"... The SG-1 [movie], I think, takes place sometime in an intermediary period between when the SG-1 movies left off and when Universe began." (Stargate executive producer Robert C. Cooper, in an August 2009 interview with SciFi Wire)
But what about the Atlantis movie? "Brad isn't producing the Atlantis movie. He's co-writing and executive producing the SG-1 movie and, in his capacity as said movie's Executive Producer, has lobbied hard to keep the project front and center and very much alive through this extended holding pattern." (Executive producer Joseph Mallozzi, in a post at his blog)