As an American who's been watching since season 2... and who needs to find alternative methods of watching episodes... I have to say that this season is that first about which I've been lax in catching up.
I too find the show less entertaining these last few seasons. Where I used to introduce the show to friends who would become hooked, lately the reactions have been lukewarm. To me, the show peaked between 4th and 7th seasons.
I think most of the regulars have become tired of the premise, no doubt Davies especially. Jupitus and Brand seem like depressed shadows of the guests they once were. Jimmy Carr hasn't had anything to contribute besides that awful laugh in 5 seasons. I absolutely love Ross Noble, but his addition hasn't injected the program with the vigor it once had. It seems like the drive for new regulars is only bringing in the standard comedian fare running the panel circuit, who seem more like they're volunteering to sit at the side of a dying relative than enjoying themselves. On top of all this, the facts themselves don't have the same punch as those in earlier seasons.