I'm using an Android powered Nexus One for work, and I like it. Mostly.
As timthefoolman says, the interface is inconsistent and difficult to get the hang of, unlike my wife's iPhone, which is consistent and easy. Worse, sometimes a touch on an icon simply isn't registered, so you poke away hoping something will happen.
Also, Android doesn't allow you to easily use a proxy server. Sure, you can root the device and then set a proxy, but even then I understand that you can't use authenticated proxies.
I work at a uni, and we require students to authenticate through our proxy server when they use wireless. iWhatevers, no worries, Android, nope. We're not about to suggest that users root their phones or install special software. It should just work, but doesn't. This problem also applies to Blackberry devices.
For me, and no doubt others, that's a showstopper. although I'd prefer not to buy an iSomething, until proxies are sorted, I'd buy one over Android.
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