OmniFocus was running extremely sluggishly for me—it took around ½ second to register each keypress, making the application nearly unusable. Searching these forums revealed nothing, making me think this hasn't been a widespread problem. Nonetheless I suppose it's worth posting for future troubleshooters.
My problem was a corrupted preference file, not a bloated database. Deleting this file (~/Library/Preferences/com.omnigroup.OmniFocus.plist) resolved the problem, and OmniFocus is snappy as ever.
My problem was a corrupted preference file, not a bloated database. Deleting this file (~/Library/Preferences/com.omnigroup.OmniFocus.plist) resolved the problem, and OmniFocus is snappy as ever.