I have a couple of questions surrounding mobile support that I am struggling to get an answer too.
Basically I wondered if the rendering of different mobile browsers is consistent, or like desktop is different. For example I have on my iPhone Safari, Opera, Chrome and Skyfire. I'm struggling to find stats that will tell me what actual browser users prefer only what OS they are using, which assumes they're using the default installed browser.
They are different. iOS is pretty consistent, but in Android, rendering varies wildly by device.
For instance, we cannot trust Android devices to render CSS3 consistently across devices. Individual device mfgs inexplicably add or remove such support. For instance, rounded corners is not consistently supported.
Sorry, I don't have any stats on this; it is mostly the word in the forums I frequent.