It is pretty simple really. I know so much about the platform that I am able to customize the phone exactly to how I like it and even with trivial effort fill in the gaps with Visual Studio and MortScript. IOS is easy, Android is configurable, WP7 is in its infancy, Blackberry and Symbian are going the way of WM.
For now I choose to spend time at my day job and with my family instead of diving deep in to another platform. I do not know how to do anything half way. Besides, my new every two is not up yet and who wants to pay $400+ for a phone...
Still running the TP2 on verizon. I had a droid X and an incredible for a while (free testing devices), but decided to stick with WM until the dual core phones with LTE are more previlent. I am expecting a few WP7 devices for testing soon, and we will see how that goes.