A couple days back when I was updating the newuprising logo, I noticed an added feature to the Blogger interface that was added with no fanfare. In fact, this may be a standard control you would find where form elements can be selected, e.g., radio buttons or checkboxes. For a browser, I definitely didn't expect this behavior. I accidentally clicked an area I normally wouldn't (unless I were utterly aware of where I was and at 8 am, I wasn't) and then did a double-take as I noticed this interface feature.
Why go to (seemingly) great lengths to talk about something so seemingly trivial, then? Transcending the OS will only be fully embraced when interface developers recreate the experience of the operating system in a browser. Doing this requires recreating every nuance that makes the modern operating system usable. So, I'd say whoever recreated that functionality was thinking of the Mac while they were repainting the OS in a browser.
ED: I went back and looked at different elements and yes, you can toggle checkboxes, however not all radio buttons or checkboxes are actually linked to their respective text. It's kinda hit-and-miss... Beta-like now that I look at it with new eyes.