I've noticed a lot of sites exhibiting these faulty semantics recently. For instance, twitter.com seems to have different content almost any time I refresh. Me

I've noticed a lot of sites exhibiting these faulty semantics recently. For instance, twitter.com seems to have different content almost any time I refresh. Me and a colleague did a quick test, submitting a GET to Twitter at the same exact time. Her screen showed a completely different set of content. Strange and troubling.