I've used Android and supported Android through numerous iterations. Here's why it doesn't make it to my daily phone use list:
1. Native Exchange support (This isn't that tough since the tech is based off of IMAP. It just takes a little organization and lining up the right syncing. 3rd party apps such as Touchdown suck at Exchange Sync still and compared to iOS is pretty incomplete.)
2. Battery life (Fortunately and unfortunately for Android, they do real multithreaded multitasking. This means that all apps can be run in background. Problem with this is battery life management which should be automated. I don't want to have to close my apps through some separate utility I download, I just want the phone to be smart enough to handle my battery life for me.)
3. Fragmentation (This is a big problem in terms of software. Android Software isn't smart enough to know that I have a larger screen or that the app was designed with another device in mind. Standardization and a walled garden help to make apps more seamless despite locking off functionality.)
4. Audio latency (Seriously, you have to ask? A lot of people listen to music on their phone. Why not have a low latency audio processor that can playback stuff right?)
5. MIDI support
6. Smarter Home Screen (It's just another thing to futz around with. Although it's great for seeing custom tailored info all at once on the phone at one time, I hate setting up widgets on the Home Screens. Even better is that if you switch Android devices by brand, you can't use the same Home Screens or keep the same stuff.
7. Solid native backup (You need a 3rd party app for this on Android when it should be built in. Part of the problem is that each phone or device you have from different brands react differently to the restoration of the backup. It's not easy enough and it's not complete enough.)
8. More stability on the OS side (Unfortunately I've crashed more Android phones consistently than iPhones. Sometimes it's the apps that crash, sometimes I get kernel panics, sometimes plugins crash the OS. It needs to just be simplified so that the OS doesn't crash as much.
9. Ecosystem (Yes, I've flushed hundreds of dollars down the drain with Android through 3rd party apps that don't really work well. Google has gotten better with the Play store but it's far from an all encompassing iTunes store which "forces" you to purchase content from them for it to work on almost any system. Apple's system gives the illusion of ease where as Google's solution seems to have constant hiccups.)