Cookie deletion in Firefox 3.5.2 always shows 0KB size even with 100s of cookies. Number of cookie files is reported OK and Deletion works. Obviously a minor problem.
In the older version of Firefox, it was easier to delete unwanted cookies (show cookies) and clear the cache (delete private something or other). They were on the same page in Tools > Options. Now it takes more steps, since one is in Privacy and the other one is in Advanced. I like to keep my computer's innards as clean as possible ( I also use ccleaner) so having to go to two places is now exactly twice as bad as it was in the old version.