I've used my iPhone and iPod Touch for some years now, but setting up the HTC Desire which comes with Android 2.2 has made me realise how much our phones have become another organ of our bodies without which I'd be unable to fully function in present day society. Only that this organ is externally controlled!!!
Lack of transparency (and privacy): To make your phone slightly useful, you have to enter umpteen account details, and download some apps. Android really scares me there, because it is not transparent who will use these details and what for. Does entering your Facebook account give Google access to my stream, contacts, likes, etc? Many services are heavily intertwined. Apps often use a built-in browser that directs you to web pages, where you can share items via e.g. Facebook or Twitter with others. A pop-up appears asking for your login credentials, then the comment box shows. Hang-on, who is now getting my login details? Is the app itself not logging this, in order to remember for next time? Is it the website that I wanted to share? Is Android it reporting to Google HQ?

If this doesn't bother you, installing new apps certainly puts me off. Even before reading this BBC article, the dialog screen giving apps a more or less blanket approval for using everything and anything on your phone made me suspicious. Apple differentiates (slightly) between the permissions an app needs. If a service does not provide location benefits, why would it need my GPS data? Not so in Android. Look at the screenshots of two rather trustworthy apps below. A lay person does not really know what's going on. How easy would it be to bait people with a free app and nick all their data in the background? 'Scuse me, but why would a bar code scanner need access to my address book?
Being part of the market war: If you haven't noticed, consumers are playballs in a massive war for market shares that rages on the Internet. Google, Facebook, Apple and co. don't give a toss about you or me! They know we cannot escape; they know we are in social and technical bondage. They are tying us down even further, giving us no real choice: either sign your apps with your blood or throw away your phone. It is little me who gets crushed by the giants throwing rocks at each other, and I don't like it. In the war between Apple's iPhone and Google and his subsidiary Android troopers, I prefer the centralistic approach of Apple, which though being restrictive, feels safer. At least it's only one company to mistrust!