6
Inside STL: The deque, design - The Old New Thing
(devblogs.microsoft.com)
The advice I've always read about std::deque is that unless you can measure a performance difference, it's better to simply default to std::vector as the cache advantages of laying everything out in a contiguous block of memory cover for many of its "Big O" sins.
Something interesting I've come across is a so-called Veque which tries to claw back some of the on-paper advantages of a std::deque but with a performance of a std::vector by keeping scratch space both before and after the used data. Can't speak to its usefulness personally, but it does look neat.
The center for all discussion and news regarding C++.