[aaronbrethorst]

> with prefixes, right now

Right, which is what concerns me. So is this the expectation?

    <img src="small.jpg" data-interchange="[normal.jpg, (only screen)], [medium.jpg, only screen and (min--moz-device-pixel-ratio: 2), 
        only screen and (-o-min-device-pixel-ratio: 2/1), 
        only screen and (-webkit-min-device-pixel-ratio: 2), 
        only screen and (min-device-pixel-ratio: 2),
        only screen and (max-width: 749px)]">

[smileyj68]

Lamentably, yes. I'd suspect the prefixes will drop off this year but we're sort of stuck with the browser adoption in this case.