Obviously Microsoft has to send out individual updates per each model phone, they can't do what Apple does, however, do they have to submit OS builds to the carrier for approval and bloatware or does MS control the OS themselves and send it out when they want to and when it's ready?
One of the major disappointments for me with Droid Bionic was Motorola and Verizon fighting for months over little stuff and Motorola having to submit good ICS build after good ICS build (like 10 total) before Verizon finally approved one which delayed the update by over 3 months, and likely closer to 6. If Microsoft controls the OS like Apple does iOS, I may look at the Windows 8 phones when my contract is up.