Start with the worse first
>> The thing about Google's dominance is that it's ephemeral.
>
> You could have said the same about MS' dominance of the desktop OS
No, you really couldn't. They own and control Win32 (and now .NET) and no other implementation can compete as they are chasing tail lights that are deliberately doing anything they can to shake anyone off.
This isn't like search. There isn't a massive world of things built on Google's search API locking us in. We could all change search engine tomorrow, we can't all change our OS tomorrow because most people use Win32 apps, Wine is amazing, but it can't really do this as it's an impossible task. If you move to Linux/BSD thinking you can continue to use all your Windows apps, you will find you are mistaken, and either go running back to Windows, or learn new cross platform apps.
What makes this much worse is they are allowed to do closed software on their own closed operating system. How the hell is anyone expected to fairly compete? With MS Office it's even worse as they have a doc spec too to use to try and stop competitors.
MS need at very least splitting into a operating system business and a software business. There should be regulation so you can do a OS and open software, or a closed software and a open OS, but both can't be closed.
It's amazing we have freed ourselves as much as we have, but this doesn't mean things aren't broken. I still every now and then, most recently with my wifes SATS marking, hit sites that only work with IE. Who knows how many Windows apps Wine can't run because of undocumented behaviour/bugs that Wine hasn't matched. It was many many years before ".doc" was blown open.
Now if Google use their monoply in search, which I wouldn't argue they don't have, to dominate another market, then there is a problem. But to my knowledge, they haven't done this yet. There isn't Google Halloween like documents with internal emails about how they can use their APIs and formats to lock people in.
A new peer-to-peer search could come from nowhere and overtake Google, or a IBM, or anyone with the money to do it traditionally. Anyway, the hardware need only grow as fast as the userbase. Google could lose their cash cow within a year or so. With MS it will be decades before we are free of their cash cows. Not saying Google don't have evil money men working there too, they do, but it's no MS. They will go down in the monopoly history books as a one of a kind.