Classic Microsoft is the king of desktop, we use their OS and we use their Office suite, and a ton of other stuff. They write all that code in-house, package it up and deploy it in various ways to our desktops.
Google is the king of the cloud, we rarely touch their technology directly, we access it over the web via our browser. Google is the biggest consumer of open source software. They load it on their servers, perhaps with the odd tweak here and there, combine it with their own stuff and leave it there on their servers. They then charge us indirectly to use it.
As Microsoft distributes its code, it is locked out of much GPL stuff. Google does not distribute its own IP, so can use this resource freely.
I reckon this makes it hard for MS to close on Google in the on-line world.
And its not just Google, I see financially viable (sometimes) on-line services that are based on open source sw cropping up all over. I guess many LAMP stack ISPs were the forefathers of this trend?
Do you reckon this open/closed source difference is important?