I recently upgraded to Gnome 2.26, and not noticing too many new features I just discovered this: Evolution 2.26.2 finally handles scrolling large mail folders effectively.
I have in excess of 1000 emails in some of my mail folders, and I have a Logitech MX400 Laser mouse which lets you disengage the "clutch" (the wheel that typically clicks in defined steps as you scroll it) so that you can do large freewheeling scrolls with one finger movement. This helps to navigate large documents, web pages, and folder lists.
Previously in Evolution, scrolling the wheel by a large amount meant that when the wheel stopped, Evolution would keep scrolling for some time as it tried to keep up with all the events.
Now, however, the folder stops scrolling as soon as my mouse wheel stops moving. Good stuff!
(For the record, Claws has had the nicer behaviour for some time, just in case you were thinking of telling me it was a new mouse driver!)