Hmm. Tough question. This is a design issue. Here comes Matt's design philosophy in a nutshell. People will argue with me on this one, as they are always free to do. Address all your mail to email@example.com.
For the most part, it's best to keep your site somewhat simple.
Someday the bandwidth and browser issues will go away. Every browser will be able to view every site, and everyone will have a fast enough connection to handle the graphics and movies and sound and all that other stuff.
But, for now, problems do exist. You don't want to create a site that even 20% of your possible market can't see.
That's the one side. But, let's face it ...
Toys are cool.
And cool draws, and cool sells.
So how do you create the balance? How do you make a site that doesn't bore people who are all shocked up, strung out on their Java, and used to viewing the world in QuickTime without alienating those who are cruising the infobahn in the slow lane?
If you're going to use some of the more advanced features of the Web, here is Matt's rule of thumb: Make the technology compelling, but don't make it necessary to the basic functionality of your site.
Some of the few time-tested (well, maybe not time-tested, but still worthwhile) rules to live by are:
Don't use bells and whistles just for the sake of using them; tell a story with the technology; and, in an over-simplification, don't waste bandwidth.
So, in my far-from-humble opinion: Use the Shockwave, etc. for games and animation and other stuff if you wish, and use it for charts with interactive pop-ups, to win more points, but don't have it be the only way to get anything from your site.
Why do some sites have a "www" in front of their address and some don't? And why do some sites have both?
Well, the sites that have both are the ones who really know what they're doing.
The www.whatever.com became a convention early on in the Web game to denote that you were going to the dedicated Web server machine, as opposed to, for example, gopher.whatever.com.
Clever system administrators decided that it made good sense to name the World Wide Web server "www."
I talked a bit about domain names in a previous "Inquiring Minds," so I'm not going to backtrack too far, but I will say this: The "www" doesn't need to be there, but it might as well be.
People expect the address to be www.whatever.com.
It doesn't cost any more to have both whatever.com and www.whatever.com (unless your Web provider decides to bill you for it), so it makes sense to duplicate.
Feel free to brand your URL with your name, like netb2b.com, but offer www.netb2b.com as well.