I did the exact same thing a few months back. I decided to give Nexus 4 and Android a try, but I ended up giving up just 13 days later. It's just not for me, who's accustomed to Apple's aesthetics and UI designs.
Many apps that come with Android are strewn with icons that are not so descriptive, and there's no labels telling you what they are. It took me two minutes to figure out where the alarm clock function is.
And then Android reeks of inconsistency. A lot of the apps I downloaded still use the Android 2.X user interface, despite Holo, the design theme for Android 4.0, having existed for over a year. Some built-in apps (yes, built-in) have their buttons on the top and some have them on the bottom. The Back button, an always-present onscreen button, frequently takes you to places you may not have been to.
There's no fine grained privacy control. When you download an app, you agree to give out all the information the app wants. You can't, for example, disallow an app from obtaining your location. You can't disallow an app from gaining access to your contacts. You have to root the phone for this to happen. Android proudly presents itself as an OS that gives you fine control over things, but apparently this aspect falls short when compared to iOS.
Switching keyboards also seems to be a rigmarole. As someone who also speaks other languages, I frequently switch between keyboards. Funny enough, a lot of the keyboards have their own way of switching, some will require you to tap and hold the space bar, some have a dedicated button. While you can pull down the notifications and select a keyboard from the list, the sheer size of the screen, and the time required to perform this, just makes it impractical.
That is not to say I dislike everything about Android. I like how I can select a file that's saved in another app and share it. I like being able to choose my launcher, which allows me to put more than 5 items in the dock. Google Now is unparalleled.
When I gave up trying the Nexus 4 and went back to my iPhone, I never looked back. I never missed it. On the contrary, when I was using the Nexus 4 I missed my iPhone every day.
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Well I don't know why I posted such a long response, probably the longest yet since my membership on MacRumors. I'm just sharing my experience and hopefully these are valid concerns that Google will fix in Key Lime Pie.