from page 5 of a document titled;
"Verizon Wireless Technical Statement in Response to Skype Petition"
located at;
http://files.ctia.org/pdf/Comments_Verizon_SkypeOpposition_Higgins_407.pdf
Phase 2 testing brings the devices back into Verizon Wireless' labs, so that we can conduct our own testing on the following services: Bluetooth, BREW, SMS, Enhanced Message Services (EMS), MMS, Wireless Application Protocol (WAP), data throughput (uplink and downling), data connectivity, battery utilization, standby time, Over the Air Service Provisioning (OTASP), and OTAPA, FOTA, PTT (if applicable), BREW pre-load applications, user interface, LBS, MediaFLO, call processing origination/terminations, and long call test. In addition, an internal user trial is also conducted during Phase 2 compliance testing. The internal trial is designed to collect more subjective feedback on the overall performance of the handset and its associated applications.
After phase 2 device approval is complete, Verizon Wireless device teams review all the test results to make a determination whether fixes to the device are so critical that a launch delay is required, or if minor adjustments to the device can be made after launch. If there are no "show stoppers" for a device, it receives technical approval and is permitted to be placed into queue for future retail distribution. At no time in history of validating device specifications and performence of a handset and its associated applications, have the Verizon Wireless device teams ever encountered a new device that required no modification from the original specifications submitted by a device vendor prior to the launch of the device...
it then goes into a good deal of marketing mumbo-jumbo about why Verizon's phased testing and feedback makes the products that they bring to market, better than that of their competitors.