Tom Scavo writes on gridshib-dev:

Technology Preview 3 of GridShib for GT v0.6.0 introduces some significant new features:

• A single comprehensive PDP, the GridShibPDP
• Implementation of a new Attribute Aggregation Algorithm (push + pull)
• Dual support for both GT4.0 and GT4.1+
• Improved logging

This is in addition to features already introduced in previous versions of GridShib for GT:

• Support for both Attribute Push (NEW) and Attribute Pull
• Blacklisting of IP addresses (NEW)
• Attribute Mapping
• Attribute-based Authorization Policy

Read the whole announcement for more details!