I don't really care for threaded Javascript in the browser, but damn can that dude illustrate a point! Cool!<p>[Edit] Ooooh, it's Mark Pilgrim, of course! Great stuff!
I really don't count Chrome Frame as "works in IE." When you say, "works in IE", it has to mean, "works in the standard install of IE." Because that is the case that most people care about. We deal with IE primarily because we can't convince corporate clients to install <i>anything</i>. If I could get them to install Google Chrome Frame, I'd get them to install Google Chrome, period.
This sounds great, but if all you're going is sending an AJAX request in the worker and stuffing the response into some element, I don't see much benefit. Most of the time you use an event handler to deal with the response so you're not blocking the main thread anyway. However, if there is any computation, DOM walking, or markup generation, I would definitely use a worker for that.<p>Unfortunately, this doesn't help the 60% of my users who really need it: the IE users with slow JS engines. I've measured 1-2 order of magnitude differences in performance between IE and Firefox/Chrome/Safari in my codebase, and there's just not much I can do for the IE users without withdrawing functionality I'm required to give them. (I wish Chrome Frame was an option, but I suspect that if they had the ability to use that, they'd have the ability to change browsers too, and they don't.)
What are some use cases for worker threads? Initially I thought there must be loads, but when I considered that XHR is asynchronous anyway, and that Worker threads don't have access to the DOM...<p>I guess it would be good if you wanted to use your visitors CPU in the background for password cracking or for the various distributed network stuff like SETI.<p>But what practical benefits do web workers provide for normal web development?
I don't really understand how's this different from events.<p>> and your web app still assumes that my browser can only do one thing at a time<p>Um, no it doesn't. What makes you say that?
Here is a short write up I did for my company blog after attending the now famous HTML5:The Future Of The Web mini conference.<p><a href="http://blog.mediaplex.com/2010/06/02/html5-why-you-should%C2%A0care/" rel="nofollow">http://blog.mediaplex.com/2010/06/02/html5-why-you-should%C2...</a>