With the addition of a plugin or two and a sane Apache configuration, Wordpress can handle some pretty extreme loads. This is not to say that it's perfect, but

With the addition of a plugin or two and a sane Apache configuration, Wordpress can handle some pretty extreme loads. This is not to say that it's perfect, but rather that performance doesn't have to be a concern if you know what you're doing. To me the biggest selling point for Wordpress is it's flexibility. I'm willing to take a performance hit for that.