If M$ gets there way you will the APPS store is that way and now M$ office (no media just a key).
No big deal... Ubuntu also has a "store" BUT I can't do nothing offline when it comes to installing as well.
Windows was ideal for this and had an upper hand above Ubuntu when it comes to offline users.
When MS will fully transform like this, they will loose me as a user.
Having to become 100% dependent on internet just like it's possible with cigarettes and alcohol it's not my way of living.
And the Solaria thing mentioned above just creeps me out... although I like Isaac Asimov stories.
Office 2010 is fine, In the far future Open or LibreOffice will probably be used in this scenario.
But they can continue this way, no problem, because just a single user will be lost: me, possibly a few others.
Don't put all your eggs in one basket.