Well, a little more searching on SO and I found a workaround here
It sounds like there's a bug in GA. But making a call to enableAutoActivityReports on GoogleAnalytics class seems to take care of it. Once I did that in my application class, the automatic screen views showed up, and the screen names were correctly mapped as configured in my tracker XML.
Note that enableAutoActivityReports says it's only for API 14 (ICS) and above. Not sure what Gingerbread is supposed to do.