It's great that these 2x res displays are becoming more accessible, but the state of web standards is dangerously behind in terms of support for them. Right now, the only way to serve images optimally for the various screens is to have the server attempt to assess the display resolution for the client using either JavaScript or CSS media queries, and then either send different HTML to different clients, with different content linked in img tags, or have exception handling for the CSS images.
This is completely broken, as a client that wishes to access various assets might be denied them by the server, which thinks it knows best what's good for the client. This system is also bound to break as clients with unexpected capabilities emerge. Instead, the server should be dumb, making all the assets available, and the client should be making the decision of which assets to request.
Apple is the obvious source of expected progress on this front, since they control the retina hardware, OS and browser rendering engine. Others are able to influence this as well. Until someone fixes this broken mess we have now, however, retina users will not be getting widespread support. We can't expect big website operators to put up with the current horrible hacks people are using to support retina displays.
That's 1) just for CSS, 2) incompatible with border-image and list-style-image properties and 3) horribly inefficient, with ugly syntax and a bunch of duplicated effort for developers (since filenames for 1x and 2x image variants are typically identical except for a few extra characters used site-wide for all 2x versions, there should be a way to allow developers to specify only these unique characters one time and avoid that extra work when possible).
This is completely broken, as a client that wishes to access various assets might be denied them by the server, which thinks it knows best what's good for the client. This system is also bound to break as clients with unexpected capabilities emerge. Instead, the server should be dumb, making all the assets available, and the client should be making the decision of which assets to request.
Apple is the obvious source of expected progress on this front, since they control the retina hardware, OS and browser rendering engine. Others are able to influence this as well. Until someone fixes this broken mess we have now, however, retina users will not be getting widespread support. We can't expect big website operators to put up with the current horrible hacks people are using to support retina displays.