Well, this won't help you here anyway. By the sounds of things, features won't be enabled by default until they're ready. Things currently aren't unprefixed until they're ready. The only way to avoid IE if the feature is unprefixed is UA sniffing.
>Yup, and it's sucky. It's no different to "this site is optimised for Internet Explorer".
It's quite different, actually. Chrome is just quick at implementing web standards, they aren't dictating things and people aren't relying on proprietary APIs.