I am intrigued by JQuery. Looks good. But my question for forum members and for the authors of JQuery In Action is this: What is the future of Web Application Development? Where do we focus our learning to best meet the needs of the future web application market?
I've been away from development for a few years, and just ramping up again, but I'm astounded by the sheer number of technologies out there now. The list on Wikipedia is quite long: Wikipedia list of Web Application Frameworks
HTML and CSS are core technologies of the web. Despite a number attempts to insulate you from those technologies, there is currently no real way to do non-trivial work without getting to know them. The good news is that both HTML and CSS are extremely easy languages to learn.
The bottom line is attempts to insulate you from the relatively simple languages of HTML and CSS leave you in a muddled state that is actually more complex, especially when things go wrong.
Some people might tell you that tools such as GWT are the "future of the web", but I don't believe it for an instant. While such tools may have a specific market segment in which they are useful, they will remain niche technologies. Moreover, even if you are in one of those niches and using these tools, you must understand the underlying technologies or you have no hope of being successful. Especially, as Yehuda pointed out, when things don't go as planned. And we all know that things never always go as planned.
And then of course there's the whole server-side alphabet soup.... but that's another show.