I have joined this list after reading @wilto's a list apart article (http://www.alistapart.com/articles/responsive-images-and-web-standards-at-the-turning-point/) and realised it was about time I stopped sitting on the sideline and get involved in the debate.
I have searched the archives as best as I can over the last hour or so, so forgive me if this is regurgitated. First, I would like to suggest throwing <img srcset> out the window and into a landfill somewhere (It's not even fit for recycling!). This reminds me if the recent semi-colon in JavaScript "debate" that erupted as a result of @fat's code in the Twitter Bootstrap project - To one or two people who are very specialised in their particular area, it seems like a non issue - and I think that is the case with the <img srcset> syntax. From a browser developer point of view it might be easier to implement, but from a "I'm just learning to code" point of view, that syntax is bat-shit crazy! Second, I'll add my support for the proposed <picture> + <source> tag version, as a much more readable implementation, and also shows similarity with the <video> tag already in use, so it should be easier to pick up. Finally, wouldn't it be more productive in the long run to define a "template" if you will for situations where alternate versions of the same "element" are required. Obviously, we already have <video> + <source>, perhaps before long <picture> + <source>, and I am sure there are others. (What was the reason for ditching the <object> + <param> tags again? because we just seem to be re-implementing them with different names!) Paul