As some others here have said, its largely not about the name. It's not like 2K didn't already own Irrational Games. They've had the option to change the name if they so wished for awhile now. The Dev team at Irrational is not physically changing in any way. All the guys are still there. So it really doesn't matter unless they fire everyone on the team from Irrational, which is quite frankly, completely irrational. Why would you rename a studio and then just dissolve it?
If there is one thing slightly upsetting about this situation, it's that Irrational Games is a much more awesome studio name than 2K Games.