I don't think any of the current commonly used tools are going away anytime soon (though I wish a few of them would).
The big trends I see on the horizon are on the backend, development side more than the frontend design side. I think a lot of sites are going to begin using native XML databases like eXist and Mark Logic to store their content instead of relational databases. Relational databases have just never been a very good fit for HTML.
I also expect we'll see more use of cloud computing with initiatives like Amazon EC2 and S3 and Google's AppEngine. Increasingly we won't think of a web site as associated with any one physical box. To a large extent, of course, that's already come to pass, but it's going to become even more true in the future.
Elliotte Rusty Harold<br />Author of <a href="http://cafe.elharo.com/web/refactoring-html/" target="_blank" rel="nofollow">Refactoring HTML</a>