Android might be popular but it does have a lot of problems of its own. One of the biggest problems that each manufacturer customizes their own version of Android for each phone which in turn causes long delays in releasing updates to the platform, some updates may never get released. While Android Market is the largest mobile phone app market currently, it is not practical for developers to develop and maintain a compatible version for each major version of Android. Sooner or later you will find that some apps for your phone are no longer available or updated.
Android gives a lot of freedom to manufacturers and operators, which is why those parties do favor Android. Apple on the other hand is extremely strict and there aren't myriad of different phones, so software and firmware updates aren't that much of a problem.
Windows Phone is probably going to hit the middle of Android and Apple in these. Microsoft is definitely stricter than Google but not as strict as Apple and doesn't manufacture its own phones like Apple does. Until Windows Phone 7.5, the platform really couldn't compete with Android and iOS either, but user feedback of 7.5 has been largely positive so that is a good sign. From the looks of it WinPhone market place is receiving a lot of WinPhone 7 compatible apps daily and I've checked that my most important Android apps do have WinPhone7 compatible versions or alternatives available.
Year 2012 will be very important to both Nokia and Microsoft, this is their chance to win people and companies over to WinPhone. This year we should also see whether Nokia's decision to partner with Microsoft pays off. Personally I am quite interested in getting a Nokia Lumia phone to replace my Android phone, which is only a year old now. But I am also tempted to wait for WinPhone 8 until I buy new phone.
