How old is TeX again?
Performance isn't a good argument in my opinion. The algorithm isn't that expensive. The most expensive part right now is retrieving all the text metrics, but you would get that a lot cheaper in the browsers rendering engine.
I briefly looked at hacking it into Webkit, but then gave up due to a lack of time.
I suspect that if you take it in pieces: first get a decent hyphenation algo into Pango, then get that into FF and WebKit, then work on the line-breaker, and then get a new CSS rule approved by the W3C... well, maybe you could get it done in 3 or 4 years.
It's quadratic in length of the paragraph, no? Not a problem for most reasonable text chunks, but browsers have to deal with unreasonable text too. In particular, O(N^2) algorithms in browser layout are generally unacceptable...
But at that point you're also asking browsers to maintain two separate line-wrapping codepaths, of which one is not used anywhere to a first approximation. Browser vendors seem to be somewhat resistant to doing that sort of thing.
Really? From my experience, ESL students often don't understand the logic behind english syllables.
My point though, is that if different languages hyphenate differently and we're talking about sites with international user generated content (Facebook or Orkut come to mind), then it's not exactly trivial to hyphenate correctly.
Also, the computation takes a while. Is this a dynamic programming algorithm? Maybe browsers should support this natively.
Yes, this is an application of dynamic programming. The computation is actually quite fast, most of the time is spent in retrieving the text metrics (put each word in a span, retrieve width and move on to the next word.) If that can somehow be alleviated it would become a feasible solution.
I agree with you that browsers should support this natively (Internet Explorer actually does.) If you are interested, I've written a bit on this subject in this Typophile thread: http://typophile.com/node/71247
edit: wait, they're there when I zoom out a couple levels. Weird.
Also: It blows up in IE9 for me though, many of the lines go on for quite a ways.