Better Caching?

WordPress does do some amount of caching. But a site being down could be related to hosts being overwhelmed by the traffic. Lots of things will take down a site pretty quickly.

Least of which is getting front-paged on Digg.com and having the tens of thousands of visitor just click onto your page. To be able to maintain sustained traffic at that pace you’d need a beefy server and pretty nifty code.

Regards

To be fair, I have also seen some pretty big, non WordPress sites, also brought down by Digg. In many cases it’s just a lot of traffic taxing the server in a short timeframe.