People are going to hate this analogy, but I see Microsoft as this...
Microsoft is that old guy in your office, who's been around forever. He's not the best, mind you, not even close, but he keeps anyone from entering his niche areas through ruthless office politics. Nobody likes this guy, he's out of new ideas, and barely gets the job done... but, we keep him because there is no other alternative, since nobody can replace him without someone, magically, figuring out all the very specific niche things he knows.
Like the old bastard, Microsoft has its claws sinked in and isn't going anywhere. We can loath them, love them, its really irrelevant, and thats what bothers me. They have such a monopoly on the OS and Office software markets, that competition with them isn't really competing, its more like fighting over kitchen scraps.
Google... well, Google feels different. They're getting huge, but they're not a Microsoft yet, and at least they have some new ideas left. They dominate the internet add space, in a near monolithic fashion, but slight competition from Yahoo and Microsoft keeps this from making me lose sleep. But, Google's definitely worrying me with their data mining practices, which are even worse than Microsoft's.
Both companies, to me at least, are a testimate to how damaging the US patent system is, and excellent examples on how a company can leverage patents to become a monopoly power in different markets.
So... my TLDR version: Fuck them both, but I hate Microsoft more.