Same reason Apple has come out with Retina – to improve the experience of using these devices and to move technology and innovation forward.
If you don't care about your work and who will use your designs, don't bother with 2x images. Having a scalable (CSS3/vectors) website is something you should be doing anyways – if not you're doing it wrong.
Lol so you're saying you should design everything in Vector format when browsers only render pixel images? LOL
Like I said...show me how people are utilizing their workflow to create "retina" quality graphics on their websites.
I don't need to get into an internet pissing match. The retina display on the Macbook Pro is a cool, novelty item for now. Most web browsers are on older, outdated technology as most people don't adopt tech early like people on this site do.
The only question I really need answered is if it's feasible to design for the web/UI on the Macbook Pro Retina. I haven't seen a solution, and others in the same business as I have the same issue.