Not sure if many of you have noticed this but sometimes when you activate the reader function in Safari, sometimes the animation would lag. I found out this neat trick to speed up (slightly) the Safari 5 reader animation.
Do this at your own risk.
Go to C:\Program Files\Safari\Safari.resources and delete or move to another location the following files:
And restart Safari. I had luck with this little tweak. The Reader animation does seem much faster and more responsive now. I guess you need a fast computer just to display the Reader without lag (if any).