I've been fine-tuning my patch for SVK which refactors the way that log messages are displayed. Basically, the patch separates presentation from logic allowing a user to format the output of the "svk log" command anyway she pleases. It also allows one to select revisions based on revprops or to modify revision properties before they are displayed (think babelfish for log messages). You can check out the latest patch posted to the svk-dev mailing list if you want to know more.
Anyway, I've been cleaning up the code a bit getting it ready for commit into trunk (waiting for clkao's new view code to stabilize first). Today I changed the way that log filters use the SVK::Log::Filter base class by using the Exporter module instead of my own home-cooked arrangement. The new code looks much cleaner.