The Surface Team would need to buy the OEM licenses from the Office Team. Surface has no insider Status and they play by the same rules as other OEMs. That $100/yr. price isn't a bad price when you consider it covers 5 devices including non Microsoft devices.
Not bad assuming you can put it on 5 devices
bosamar, why give away what you can sell? I don't understand why anybody should expect that Surface Pro or any machine should "come with Office." That isn't to say I'm not grateful for Office being on the Surface RT but that was a huge factor for the RT considering you can't install it (or any desktop app) on your own. Sure it could help Surface sales but at what cost to Office? An included trial period would probably be a very good compromise. As I said before the idea of subscription Office hasn't caught on yet and a limited time trial might be a good way to promote both things.
I tend to think of it like most other devices, cameras do not come with SD cards, toys do not come with batteries and computers don't come with Office. There are always exceptions but they are just that, exceptions that are usually promotional or introductory. Personally I am one of those people MS is trying to convert. I have Office 2007 and it will go from computer to computer until I receive a free or discounted copy of a newer version of Office at some point. If that doesn't happen, well, Open Office or other free alternatives aren't objectionable to me. Not good for MS sales but for personal use I don't need the latest and greatest Office just a somewhat recent version.