People are complaining, but they have a much more complex code, and run a debug - Everytime they fix one thing, the debugging software finds another problem, probably more gamebreaking than the last.
Go on, keep finding more and more glitches, every glitch you find delays the patch by a further day at least.
They've said it's very complicated, they've said it's not very stable on the 360, and you have to respect that.
If everytime you fixed something, you'll have broken it another way, you would do it a certain amount of time before you give up. No-one has really quit from the developer's studio, so you see, they're frankly getting a bit pissed.
Acknowledged problem = +1 day to 1 week