The re-planning of the GlassFish 3.1.1 Open Source Edition release to accommodate more fixes is now complete and the wiki pages have been updated (plan, roadmap). The 1st Release Candidate should be here by July 7th.
In addition to the original goals such as AIX and Solaris Express support, JDK 7 is also on the radar, as well as fixing numerous bugs, including those reported by the community.
In addition to improvements to the embedded API many developers will should be interested in the tentative list of component updates - EclipseLink (2.3), Metro (2.1.1), Woodstox (4.1.1), Mojarra (2.1.2), Weld (yes, 1.1.1!), Hibernate Validator (4.2) and Jersey (1.8).