I noticed that Safari started rendering common web pages in a funny manner on two different Macs that I have. One is a Macbook Pro and the other a Mac Pro desktop. Yahoo and Google would appear all excessively bold or all italic and not at all look right or acceptable.

The computers are all running OS X 10.6.3 "Snow Leopard"

Turns out that "Arial.TTF" and "Arial Bold.ttf" got deleted somehow on these two computers. I restored Arial through Font Book and got my web mojo back.

So questions:

1) Anyone seen "arial" strangely randomly disappear? The only thing in common is these are the only two computers out of eight on site that recently got Adobe CS 5 installed. Has anyone had CS 5 delete arial?

2) When I restored arial with font book, it goes into User fonts rather than the All fonts. Can I use Font Book to restore a font in /System/Library/Fonts or do I need to do that manually?

3) I located THIS article on the web regarding OS X fonts. Essentially, Snow Leopard did away with the older .dfont format and replaced with open True Type. There is a minimum font list, but Arial is not among them. Arial is installed by MS Office.

4) Why are web sites affected by Arial being missing anyway? If I look at the HTML source for Yahoo for example, "arial" is specified by name only in an ad. Yahoo itself does not specify a font name. In my Safari preferences, I have Times and Courier specified as the default font which is the default for Safari when installed. How does a missing Arial screw things up anyway?

Thanks in advance.