This page enumerates performance improvements (such as faster performance, lower memory usage, and reduced disk usage) that affect the end user (and not just developers). Also, omit issues that only affect non-final builds.
For a general list of new features in 3.0, see OpenOffice.org 3.0's New Features, An Early Look.
For a general list of new features in 2.4, see New Features in OpenOffice.org 2.4.0.
These patches are not upstream. :(
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