Stan Lee and Jack Kirby did the same thing with FF#20 to 50 something back in the day, generating an extraordinary amount of characters without fully fleshing them out... And I believe their motivation (which I read in an interview a long time ago) is the same as Bendis' is now. Get the characters out here now, let people know they exist and have them clamor for more. These are introductions, like how Gambit did in Ultimate X-Men #14-15 (I think). This is the handshake. The conversation comes later.
In summary: The stories aren't bad if you just don't like them due to the seeming constant assault of "new" characters. (Peter's dramatic real, non-costumed life has always been well done.) They're opportunities, the same way Lee and Kirby put them out there, a step into the doorway of something more.
I'm sticking with Bendis on this one.