What would be nice is if Google released an Android app that does the same thing as Glass (ie. ___location updates and push notifications), for testing purposes. It wouldn't be as nifty as having the thing on your head, but pretty much all the use cases covered by the API would work on that.
Yeah, I assume that works if you want to test how cards display, though there does not seem to be any interaction.
Considering the API only allows viewing cards, taking pictures, sending your current ___location and taking textual input, there's nothing that prevents them to have a glass implementation on Android to test things out, other than the time/resources to develop such an implementation.
