Neither the small computation or a email stamp purchase are the brain childs of microsoft. However this idea is gaining mind share because the redmond machine has put its weight behind it.
I think the government might like the idea of email postage, since it would serve as an entry point into the taxation of email. Plus a systematic government postage system could underpin email tracking, since postage key (stamp) and key checking would probably not be anonymous.
Even if a national email postage system is used, I don't think everybody would use it, since it would be hard to stuff the free email cat back in the bag. There might be two systems, where you only allow free email from known friends and family, but use the postage system when going outside of known sources.
As I read it, it's not about revenue, it's about bandwidth. This is the same idea as parking meters. Meters don't yield a lot of revenue -- they're designed to keep parking spots on city streets turning over.
But IMO, applying the idea to email is just plain whacky. It's like requiring pay phones in everyone's house to cut down on telemarketers. Regulate the spammers, but leave private folks alone.
If microsoft servers became the e-postmaster for this email postage system I wouldn't support it. I assumed the final spec would be governed/controlled by an entity like ICANN (which oversee the domain name system).
As a Taxidermist I look at hundreds of Whitetail Bucks every year. I know that I have seen many different ways people judge the size of racks on live deer. I think for the most part they all are pretty close. I'm going to give you some measurements that I have noticed being right on in just about every deer. We have used it in the last couple years and have only been off by about 5-6 inches. We do study the deer while bowhunting so we get a little more time to look at them....