Given how the last few weeks have played out, my wife speculates that:
1. In the weeks preceding the finale, Jim and Pam will split up.
2.
Then "ten years in the making" documentary promised at the end of the most recent episode will be the focus of the final episode. (Although why the documentary crew will still be following them at that point is beyond me.)
3. Jim and Pam will reconcile as a result,
seeing as the focus of the doc will be how true love blossomed at the reception desk.
I almost wish she hadn't shared her thoughts, because I'm now convinced this is the exact plan that Greg Daniels had in mind when he said this would be a "big Jim and Pam year." The British series was certainly sentimental -- although generally willing to undercut its sentimentality with some snarky talking head -- but I have to imagine that an audience manipulation of this magnitude would leave Gervais cringing.