In addition, do you have suggestions for pricing apps? The following indicates average price at ~$3.50 USD: http://techcrunch.com/2010/01/26/android-market-pricing/ (I know it depends on the app's functionality and perceived worth to customer, but I also imagine people would be much less likely to spend $39 USD for an Android app than they would for an OS X/Windows application with similar functionality/intent.)
Finally, is it realistic to develop solely in an emulator without having a real device, and if a device is needed, what would you suggest as a lowest cost option to start with?