John Gruber, commenting on Dave Winer's post on why he uses Android rather than iOS:
Fear of Apple is about losing control over the software on our computers. Fear of Google is about losing control over our privacy.
That's the best, clearest description of the difference I've seen. I don't care what anyone else uses. But I value my privacy more than I value the ability to compile the kernel behind my operating system.
And, I'd also suggest that the control over the software in Android etc... is an illusion for most people. The vast majority of people will not be writing their own software, nor are they going to be compiling anything from source. They're at the mercy of software developers and corporations just as much as those using non-Open software.
I believe that openness has more do with a person's ability to do what they want to do, rather than with who gets to compile the software they use. Part of that ability-to-do-what-you-want involves not having to sell your digital soul as part of the process, which is what Google wants you to do.