Here's a list of the most noteworthy things in the RAP 3.0 RC3 release candidate which is available for download since June 05, 2015.
Exploiting some of the new theming features, the ToolBar has a new default look combining all items to a single visual element. Single items are still distinguishable when hovered with the mouse. The previous look is also still available, simply by setting the SWT.FLAT style flag. This flag is used by default in workbench applications, so these will still look the same. The business theme is also not affected by this change.
This list shows all bugs that have been fixed for this release candidate.
The above features are just the ones that are new since the last milestone build. Summaries for earlier builds:
To assist you with the migration from RAP 2.x (or 1.x) to 3.0, we provide a migration guide.