Check out Adobe's Flash Builder FAQ which has more information
What are the editions of Flash Builder 4.7? Adobe Flash Builder 4.7 Standard Edition: Flash Builder 4.7 is a professional-grade development tool for rapidly creating games and
applications for the web and mobile devices using ActionScript and the open source Flex framework. It includes support for intelligent coding, interactive step-though debugging, and multiplatform publishing workflows.
Adobe Flash Builder 4.7 Premium Edition: This edition has all the great features that Standard offers plus professional testing
tools, including profilers, network monitoring, unit testing support, and command-line build support.
Why use Flash Builder Premium Edition over Flash Builder Standard Edition? Flash Builder 4.7 Premium adds professional testing tools, including profilers, network monitoring, an automated testing
framework, integration with Flex unit testing, and command-line build support.