I&apos;m re-submitting this post since I had to blow away the original one when I had the HTTP compression issues. The original, posted on August 19, 2007, can be found via <a href="http://209.85.165.104/search?q=cache:Dk7SsRjlOJwJ:www.reybango.com/index.cfm/2007/8/19/4060-of-Yahoos-Users-Have-an-Empty-Cache-Experience+yahoo+empty+cache&hl=en&ct=clnk&cd=1&gl=us">Google cache</a>:

With RIA&apos;s becoming so pervasive and developers just going full tilt in embracing toolkits that help build these wonderful apps, its still extremely important to take into consideration site optimizations that actually make your site usable.

Take for example the age old adage of the "files are cached on the user&apos;s computer". Well, Yahoo seems to have done a good job of dispelling that thinking by doing some research that shows that:<ul><li>40-60% of Yahoo&apos;s users have an empty cache experience</li>

<li>~20% of all page views are done with an empty cache</li>
</ul>
Holy crap! 40-60%!!! Yahoo&apos;s audience is so distinct that these figures really are compelling and should be considered when designing your site. Here&apos;s the link for the full article:

<a href="http://yuiblog.com/blog/2007/01/04/performance-research-part-2/">Performance Research, Part 2: Browser Cache Usage - Exposed!</a>

It really is enlightening.