Since installing Mac OS X 10.6, whenever I empty the trash, it takes about 50x as long as it used to under 10.5. I just emptied about 100 files (totaling 50 megs / all local files), and it was about 20 minutes.
It feels like its doing a secure delete, but I'm just using the "Empty Trash" option (click on bin -- choose empty trash). Is it possible that the secure delete is turned on by default?