I think that Bendis is totally burned out with the Avengers. The guy did Avengers #500 - 503 + Finale, Avengers #1 - 18 + 12.1, New Avengers #1 - 64 + 3 annuals, Illuminati, and Finale, New Avengers #1 - 17 + 16.1 and 1 annual, Mighty Avengers #1 - 20, Dark Avengers #1 - 16 + annual, Avengers Prime #1 - 5, Dark Reign: The List - Avengers, New Avengers: The Illuminati #1 - 5, and one of the US military New Avengers comics. That's over 160 individual issues of various Avengers books within the span of 7 years, double the amount a typical writer does on a run on one book.