Integrated updates

I saw a recent complaint from someone that Apple should open up their system update interface to other developers. I agree, this should be done. It would be a boon for consumers.
However, it should also be done for Windows as well. Currently only Microsoft products (and a few drivers) are integrated into Windows Update, which is a real shame.
What hurts on your typical PC is the sheer number of update mechanisms that are installed on a machine in order to ensure that software is kept ‘up to date’. Typically each of them installs their own scheduler that performs all the update checking tasks. Liveupdate, jusched, realsched. There’s probably a scheduler for you anti-virus software as well. The complaint is that on Windows 2000 and newer there is a perfectly good task scheduler on the machine (there was one earlier as well, but that’s not the issue, really). It can do everything that you need for scheduling – one offs, once a week, once a day, once an hour, every third Thursday of the month. Why can’t developers use it?