I'm using Adobe Edge Animate to design and build html5 web banners in. Currently working on one which contains a animation. I got the animation in mov. with transparent background. But it seems that Edge only support MP4, OGG and Webm format - so there for my question. Does it even support file formarts which support alpha channels?
It will support an animated gif with alpha. I have had luck with exporting after effects as a png sequence w/alpha then create an animated gif out of the png sequence.