In this post on Google Plus that I can only describe as calmly and gently aggressive, Google's Eric Schmidt explains how to convert from iOS to Android. The explanation is an extremely detailed step-by-step tutorial, in-depth enough that a complete novice could follow carefully and do everything he suggests, but also enough that experienced users will almost certainly find useful tips to ease the process. He even offers alternative solutions should certain issues arise.
If you're looking to transition from iOS to Android, Schmidt's guide looks to be extremely useful, but I suspect than an even more significant audience might be Android lovers who appreciate a dig at iOS that doesn't even feel like a dig. After all, Schmidt doesn't need to say anything directly negative - the way he talks about it, switching to Android is an inevitable, obvious choice. The only thing keeping people from doing it was the lack of a good tutorial, right?