I agree with brad327 I would prefer to build my OS the same way. With Windows XP for example for your computer to be able join a domain you had to go to XP Pro (you also need Pro to do server-like functions like terminal services and so on). I would prefer to buy windows (at the "home" pricing) without IE, WMP but with "join domain" capability.
This may sound ideal but unfortunately it is not going to happen, they rip off enterprises with Professional editions, that's why most of them haven't upgraded from XP pro, and probably would have stuck with Windows 2000 Pro if they have added USB 2.0 support. When you are a professional you don't mind your system looking obsolete, but being technologically obsolete, and this is not true for many aspects of Windows XP Pro.
Back to Home users, Microsoft has a large market share and wants to maximize profits from it. I think that things are going to be the same for desktop and notebooks. In netbooks though they want the user of Starter Edition to be annoyed, to feel second class, they didn't remove IE8 or WMP (which could be easily solved with freeware programs that are better than MS's) At first they wanted to limit the OS to 3 apps running, and then they said that you cannot change the background, both of them imo very annoying... So yes they want to get rid of the old distribution system (that of Win XP) and maximize profits in the netbook market.
This system of Anytime upgrade is the only way to ensure that large OEMs will ship netbooks without Linux, without WinXP but with a version of Win 7 that the upgrade will be purchased by the end-user which would normally choose 9 out of 10 times Win XP or Linux over a non-upgradable Win 7 starter netbook. That said everybody wins except the end-user.