Dave Winer suggests that using iOS has a flip side -- Apple controlling mobile through the App Store:

Right now it's the only open source mobile OS that has a chance against IOS. If there is no alternative to IOS then Apple will have exclusive control over what makes it to market. That is a future none of us should want to live in.  

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I don't like Google any more than I like Apple. But at least they don't control the channel of apps to users of Android. That's a huge deal. It makes up for a lot of Android's inadequacies. And if Google fucks us, let's find another home.

John Gruber points out that you could argue the Flip Side to Android is your loss of privacy to Google:

But, to quote Neil McCauley, there is a flip side to that coin. Winer’s perspective is that Apple is the bigger threat. A different perspective would be that Google is the bigger threat, and that using Apple products is a way to better protect our privacy and personal information. 

Fear of Apple is about losing control over the software on our computers. Fear of Google is about losing control over our privacy.

These are both good arguments.  Apple's control over the App Store has some positive effects, but it's clear that it puts a lot of power in Apple's hands and they can and will make capricious decisions that we may disagree with.

Google absolutely wants to know as much about you as it can and sell you in aggregate form to advertisers. That's their business, and if you don't like that, then storing most of your personal information on Google's services is probably scary.

I think it's a mistake to link Android only to Google. As has become entirely clear, the open-ness of Android is to be open to the manufacturers and carriers who often close it with respect to its customers. Putting your faith in Android is not merely to trust Google, but to trust Motorola, HTC, Samsung, etc. and Verizon, AT&T, Telus, Rogers, Sprint, T-Mobile, Orange, etc.

Pre-iPhone mobile phones were entirely controlled by the manufacturers and carriers. The iPhone was in many respect a great liberation the mobile phone market. Although Apple retains the same powers that the manufacturers and carriers once did, they attempt and mostly succeed to use those powers to improve your experience as a mobile customer (and secondarily to profit from it), and they keep everyone else's hands outside of the cookie jar.

Putting your faith in Android is putting your faith in the mobile phone ecosystem that kept a stranglehold on your phone for years and years before Apple came along. If you think those people are more trustworthy than Apple, you're probably drinking the Open kool-aid.

If Google used its Android powers to force the carriers to make the software open to their customers, to allow people to install whatever they want without worrying about carrier agreements, to prevent spyware installed by carriers, to encourage phone manufacturers to update to the latest version of Android -- if Google was open to customers then maybe I'd agree.

For me, Dave Winer's argument doesn't hold water. I don't see the value in wresting control away from Apple just to hand the power to a larger and shadier group of companies.