Personally, I would go for the HTC Desire.
My phone history, went from a iPhone 3G to a HTC Desire. I've used the iPhone4, a friend of mine has one and recently had a BBQ at his after playing Golf.
Reasons for
me preferring the HTC Desire
- I love HTC Sense, this is HTCs UI. The contact list on the phone pulls all your contacts information from Facebook, Twitter, Flickr and you can look at their photos directly in the phones gallery, rather than loading up Facebook and navigating to them.
- As someone who works in FMCG, email to me whilst out of the office is vital. I can set out of office, send meeting reqests, see all emails in conversation view - couldn't do that with my iPhone 3G, not sure if the iPhone4 can as my friend didn't have his email setup.
- Ability to install applications off the SDCard or via QR codes. Unlike iPhones where every application has to come from the App Store.
- I can install any application I like, including Fennec (Mobile Firefox). Apple will not allow alternative web browsers that don't use Safari's inferior engine (Safari doesn't have V8 JScript engine unlike Android).
- Full Flash support, so you can view every Youtube video. The Apple Youtube application only shows select videos that have been coded to the supported codec.
- Google Services data sync - you have to pay for MobileMe on the iPhone for a similar service.
- WiFi tethering on Android, it's locked down on the iPhone, so the carriers can charge you to use it.
- Android Widgets, I can control my hardware from my homescreen (such as turning off the wireless controler) to save battery and without having to navigate though several menus.
- Chrome to Phone - push links, navigation directions and applications to your phone from your desktop via WiFi or cellular network.
Only thing I miss about the iPhone is the iPod UI as Android/The Desire lack a decent looking player.