Shouldn't last year's "The Gayest Music Video Ever" replace the Conway Twitty rib in the title? It was just as long as Twitty and just as much filler.
Thought, personally, I'm not feeling the hate most the to thread is about the show. Yeah, it's not a personal favorite or anything, but I get a decent amount of laughs out of it, about as much I get out of South Park these days. I used to dislike the odd self-righteous politics the show seemed to have a few years back and grew weary of some of the lamer humor and overlong cut-aways, but I've noticed in the past 3 seasons that the writers of the show has become increasingly aware of some of its shortcomings and the show still has a unique edge (even if the edge is more like a blunt mallet)
The show's hasn't changed much one having its cake and eating it too when it comes to racial and religious humor, aware of its own hypocricy in making fun of and digging for touchy subject matter and jokes while also including statements and actions that its wrong (mostly). Shock and lowbrow/toilet humor have been pretty constant, though the writers can be witty and sharp when they want to. However, I have noticed that the writers have been getting more varied with Brian, who was often the moral and political center of the universe. He's been shown more flawed and egotistical in later episodes, and his recent rivalry with Quagmire has added a bit to both characters. Heck the show's also admitted that many of their skits based on other pop-culture material basically consists of ripping them off and sticking Family Guy characters into them. Even so, some of the skits and other sequences in the show have a noticeably higher budget look to them.
Most significantly, though, I've noticed a concentrated effort into trying to add actual drama and emotion to the show in the past two seasons. This last episode is definitely a telltale sign of it. While it doesn't always work, it does help to well-round and solidify the characters in the show and adds a few other extra layers to the show as well, though it sometimes clashes with the usual madcap atmosphere of the show. Though it doesn't appear to have affected the constant supply of Jew jokes.
Regarding this recent news of MacFarlane pulling the plug on the show, it is surprising since I don't think any of the spin-offs are really going to take center stage (American Dad, maybe) and Family Guy is still the #1 rated show on that block. I think he'll wait for she show to slip to #2 in ratings before canning it. Don't think there would be a fan write-in if it's cancelled by the creator–only if the studio declines to renew for another season.