Update: 11th December 2007 As per the new spoiler posted in the Spoiler Section. I can now confirm this as true.
I've just had some interesting info from a source, which although I believe is correct due to their track record, I will post it in Rumours until I get confirmation from another source and then move it over to the Spoilers section. I can't post the full contents of the message but I will summarize it here.
- There are no Sawyer flashbacks/flashforwards in the first 8 Episodes of next year
- Sawyer is not one of the Losties that got off the island
- The fact that he is not off the island does not necessarily mean that he his dead or won't at some point in the future, however, when the Jack/Kate scene takes place at the end of Season 3, Sawyer is still on the Island.
Source: DarkUFO