The future started more than two years ago, actually. You can experimentally verify it for yourself -- my understanding is that they use a combination of heuristics and actual evaluation.

For example, putting an invisible div on your web page stuffed with keywords is usually a one way trip to smackdown city. Put an invisible div on your web page and make it visible in response to pushing a button and they will index the content much of the time. They are known to spend extra resources to make sure popular techniques do not cause their algorithms to break. (From a SEO perspective I'd suggest being one step behind the cutting edge on innovations like that. 100% JSON site? Cutting edge, probably uncrawlable. Shopping cart rendered using Prototype? Works fine.)