A year since I last looked at the data for BerryReview, Carrier Billing remains a significant advantage for selling apps.
Comparative purchase rates for Pixelated Plus are shown in the above chart for the seven largest carriers in North America. Of these seven carriers, only Verizon and Sprint do not yet support carrier billing. Across all these carriers, customers who have access to carrier billing are 2.14 times a likely to make a purchase.
The measurements in this chart are relative to the number of purchases at Verizon Wireless (the largest carrier), such that Verizon would always have a value of 1.00. The number of purchases is based upon purchases of Pixelated Plus from January-March 2012. Normalization for carrier size was based on data from the free application Pixelated over the same time period. All data was collected through BlackBerry AppWorld at the time of download.