More importantly than waiting for new browsers to support all of these wonderful new technologies out there still lies the enormous problem of variety that exists out there. The more browsers upgrades we get the more fragmented our user clients are, as explained in this Smashing Magazine article: Old Browsers are Holding Up the Web.
It's one thing to have to keep up with all of the technology out there, but it's another to have to hold onto all of the old knowledge and still use it with the new stuff. The matrix of can/can't/can-in-this-scenario-but-only-if-the-stars-align is becoming overwhelming and frankly expensive.
The web field talks about it, but the people who need to really understand it never seem to. It's like there needs to be a TV commercial to target the every day web users that don't understand upgrading their browsers. That is where those users are. Even location based ads for targeted services could be a solution. A consumer at the grocery store receiving an incoming explanation of the savings they just made by certain actions is an example of how this is implemented in other industries and seems to work alright.
Short and quick explanations of how epic it is to upgrade, with a URL that explains how and how to keep them upgraded. Many people don't even know there are more than 1 browser or what a browser is, so we could make the page educational and help all developers out there use the amazing tools we keep learning about but have to keep holding back. The best example I've seen of this so far was also a Smashing Magazine article, but if you have seen others please share them!
Moving forward we must help momentum to catch up to technology which will provide a more automated solution (many already have).
I can't wait until browsers are all cloud based.