Alex
You are certainly correct in criticizing what many documentaries are guilty of, all shots and no story. Deep Blue had a bit of luck by having even more stunning shots that weren't available when Blue Planet was made.
However, I'll have to say that Blue Planet did more for u/w natural history filmmaking than any other series besides that of Cousteau's films from the 50s and 60s. Sure IMAX films have the wow factor, but I find most of them fluffy myself, especially Galapagos and Coral Sea.
I think the problem isn't the docos or films but viewers like myself, who want a certain something to keep my interest, if we don't get it, it's boring. Definitely NOT more discerning but certainly harder to please.
If you ever have time to go to Poitier in France. Try the magic carpet ride with "Voyager du Ciel et de la Mer". With a ride like that, I really could give a crap about storyline. But that's a rare thing. 
Of course the other problem is that the script sometimes is perfect but they couldn't get the shot. That Baikal shot of the seal took 3 weeks. They just couldn't get it close enough to get more decent shots. A lot of times in these sort of locations, the idea is many times better than the actual result. But sometimes you get the March of the Penguins, a humanized doco. I loved the cinematography and behavior but disliked the boring emotional violin scenes.
There's another movie coming out in 2008. I'm not allowed to talk to much about it but it is online now. The same director and producer of Le Peuple Migrateur are shooting a film called Oceans. And I'll just say that the shots look awesome. 
Though it would have been nice.
