Yes. Jim and Pam are actually going to get married this season on The Office.
That's finally been established, so the only question is when. The current rumor is sooner rather than later. Episode 4 of the upcoming Season Six, according to TV Guide.
Why the rush? Because Pam doesn't want anyone to know that she's expecting: "Hilarity ensues when an unlikely party becomes her accidental confidante. No, not Phyllis."
Who could it be? All we know is it should make for good Office quotes.