According to Think Secret, it just may be. It looks like the
majority of engineers who had been working on Aperture have either left or
been reassigned to different projects within the company. Think Secret goes on to claim that the applications
development was "...a mess," according to a source, and that developers from Shake and Motion had to be
brought in to do a little damage control.
I haven't used Aperture, so I can't speak for it's supposed buggieness. It did experience quite a price drop with the 1.1 update, so maybe Apple is eager to move existing copies.