Once you get settled on the site and it starts getting some hits you should install supercache
http://ocaoimh.ie/wp-super-cache/
Wordpress is good at handling moderate load but for slashdot or digg level of activity you need supercache to even have a half a chance of staying up for the rush. The standard wp-cache module is not really anywhere near as good at keeping the site up. Even traffic from stumbleupon can bog a wordpress site down without supercache.