If the resulting sites can't handle a traffic spike, it's not that great a tool, is it? No one wants a hammer that shatters if you swing it too hard...
Being optimistic, it might just be a hosting problem.
Ya, to be fair I've seen Wordpress blogs go down under an HN spike, as well as a lot of stuff using socket connections for each user. Not many people build products expecting 100+ people to simultaneously use the site on day one.