Mark Evan's points about networks owning content in a twisted way supports my views on why AOL and MSN would be a great marriage. Carriers need to have something to offer other than dumb pipe that adds value to the service offering.
MSN will be the tech. AOL/TW will be the content. Microsoft stops having to worry about content deals, or even how to make them. TW already knows how and with whom to do them beyond their own. This is akin to being like P&G is as category captain in the grocery story, in this case TW/AOL plays content captain, determining the mix of what gets the best position in the browser, while MSN figures out the best ways to serve it up. No one restricts access to the rest of the content, but where the money and support goes (i.e browser real estate) is determined.
For TW/AOL their upper echelons don't have to figure out what technology to invest in. Microsoft does that for them.