Apple does it by moving slow as molasses and only releasing a single version every year. There are multiple versions of Android a year. A long beta test would also just compound the problems for goobers on skinned phones, they'd have to wait even longer to get the updates.
Aside from that, I see it as a non-issue after ICS. If your app is optimized for 4.0 and Holo, your app still looks and functions great today. Unless you're doing some BS hacks that break with a new release because your coders are CS dropouts.
CS is cascading style right? I remember learning that in HTML class back a ways. Hated it though; preferred doing it all manually.