The NBC promos have not been subtle. "On the final episode of Ed, it's the moment you've waited four years for. America's favorite love story ends with a wedding finale." (Those nuptuals are tonight at 9 pm/ET, by the way.) That seems pretty clear cut, and yet, there's been no official cancellation of the show. So on this last day of filming at Ed's Stuckeybowl set in New Jersey, it's a bittersweet moment. "I think we look at this as a series finale," says exec producer Rob Burnett. "The story began with Ed coming back to Stuckeyville and asking out this girl who didn't know him and today we're filming their wedding. It feels to me, and to all of us, this is the end of the story."

To say that there have been a few obstacle-filled chapters along the way would be an understatement. For Carol (Julie Bowen), it began with an arrogant boyfriend, continued with a supremely cocky fiance and briefly detoured for a sad-sack — but very persistent — school accountant. Not to be outdone, Ed (Tom Cavanagh) traveled a winding romantic road that included some speed bumps named Bonnie, Frankie, Liz and Kelly Ripa.

What could have been a one-note series about Ed and Carol's roller-coaster relationship instead became a pleasantly surreal world populated by very patient best friends, eclectic bowling alley staffers and a few spastic high school students. "The cast is very strong and when you have that, you're already 80 yards down the field," says Burnett. "A lot of times we'll write something and you audition people and you're, like, 'Oh, my God, this isn't funny.' And then suddenly you get the right person in there and it's great."

There's the right person and there's also, arguably, the right time for a series to ring down the curtain. "It's been a terrific run," NBC president Jeff Zucker tells TV Guide Online, "but the odds are this is its final season." Zucker also confirmed that the actors have been told they have permission to look for pilots. Nevertheless, he does add that "we're going to leave ourselves a little flexibility for when we put the schedule together in May."

Sidestepping the uncertainties of network programming, Cavanagh has taken a more reflective outlook. "When you're fortunate enough to be given something so great," he says, "part of the moral contract is you gotta treat it with respect. I think that means not overstaying your welcome, and I don't believe that we have. If this is the time to call it, certainly, I think everybody can be very happy and proud about what they've done here."