GeoTools 2.6.x looks to be focused on quality and performance.
As always the scope and timing of releases is set by you - the members of our community. There is a host of interesting "unsupported" modules that can make it into this release based on time and funding.
We have tossed both gt-swing-widgets and gt-swing-widgets-pending in the bit bucket as their module maintainers have stepped down. We have salvaged a new gt-swing with s strict mandate to provide user interface classes for our demos; nothing too fancy - just enough that we are not wrecking out examples with user interface code.
We have updated out data model to support the constructs used by the symbology encoding specification; and in a few isolated cases received patches to hook them up to the render (such as Unit of Measure support).
We expect the render to gain additional capabilities as members of the public supply patches.
Andrea Aime has been cleaning up one of the top issues on our technical debt page - cleaning up after the transition to GeoAPI filter done way back in GeoTools 2.3.
There is a Technical Debt page with details of some "undone" work (often work left over when a commercial funding ended for a specific task).
A GeoTidy project has started up based around the GeoTools referencing modules; we will see how this project goes and will continue to work on collaboration.
Next Generation JDBC
Thus far the "Next Generation" JDBC DataStore are worth being excited about (making use of prepared statements for both speed and security). These are also available on the previous 2.5.x branch.
(X) N-Dimensional GridCoverage
We also hope to see an introduction of a "N-Dimensional" GridCoverage "DataAccess" API. This work was started by Simone but does not appear to be finished in time for release.