This was an interesting article, from a network and systems architectural point of view. I don't think that a lot of end users will care that Bing is built upon a fairly lousy network and systems architecture -- but that doesn't directly relate to important issues in the user experience.
Microsoft is at a disadvantage here because they try to build everything on the Windows platform. Windows was designed as a GUI for a single-user operating system. Cloud computing is not it's forte'. But, Microsoft is expected to "eat it's own dog food" by trying to make Windows do all sorts of tasks for which it was never intended.
Google's platforms are designed for scalable and distributed applications -- but I wouldn't want to see then shrinkwrapped and installed on home PC's. Each platform has it's strengths and weaknesses.
I'd rather see Google and Microsoft talk about how each of their platforms serves my needs better. The back end of these platforms is interesting from an intellectual standpoint, but what I really want are better search results.