Well, let's see. Windows XP was released on October 25, 2001, Apple OS X.0 was released on March 24, 2001. . . so those would be comparable. However, Windows XP was superseded by Windows Vista on January 30, 2007. At that time Apple was still shipping OS X.4 Tiger. It was superseded By OS X.5 Leopard on October 7, 2007. So, In answer to your question, Tiger is no longer supported with security updates and the Safari version that shipped with it will not be fixed. However, Any Mac using OS X.6 "Snow Leopard" which was released on August 28, 2009, or later will be receiving an update to fix the issue.
That being said, according to Chitika, the percentage of Apple Mac users who are still using OS X.5 Leopard or older is less than 2%. On the other hand, for-q-clinton, they report that almost 19% of Windows users are still using Windows XP!
Ping to my comment #30 above, almost time-coincident with yours.
I'm sorry Windows XP is such a great OS that so many people are still using it and Snow Leopard apparently sucked ass because no one is using it. Also how many people are still using the original OS X.0? Yet 19% of the users (according to you are still using XP).
It's not about the % of people using it...it's about who has supported their OS for the longest period of time.