Considering how long the development has taken I also share concerns about the game engine and what technology it is/was aimed at the time. If we go along with Oleg's theory that work did not start on SOW until late 2007 then the best GPU at the time was an 8800GTX and CPU's were intel dual core's with Quad's first appearing later the same year.
On the face of current information received i would estimate a release around late 2010 or maybe early 2011 though it is very difficult to get a real grasp of development with so little and often conflicting information. Hopefully when we see actual inflight shots in September we may get a better idea of development progress, or if we start to see some form of marketing i.e an official website which usually indicates a release within the next year or so.