Quite a few studios employ what is best described as 'seasonal workers', who do code monkey stuff during the development phase, and are laid off afterwards. The sad thing is since so many fresh out of college, wide eyed programmers have dreams of being in the gaming industry, they accept the $45k a year to have horrible hours and treatment only to be tossed at the first mention of "going to gold". It is really a race to the bottom with these guys.
It's pretty much like that in the entire media/entertainment industry, unfortunately. I know a few people that got great gigs fresh out of college only to end up working retail a couple years later. All contract work these days. Been that way for a long time too.
Take-Two says they'll continue the Bioshock series. With Ken Levine and most of the original staff gone, well, they were the ones that made those games great.
I know I'm in the minority when I say Infinite is my favorite in the series. I love the setting, time period, and the story in that game. Though it's well known that it had some major snags. A lot of what was promised didn't get delivered. Which motivates big publishers to begin seeking out fresh blood.