I started my career coding HTML 4.0 way back in 2000. The web was hot at that time (btw it has become hotter now :)). HTML seemed easy. You write tags and see the changes, no wait time,no fun ;) .
Java was the hot buzz word. Every other person was crazy about learning Java. Applets were kind of geek thing. It was kind of prestige issue to learn Java. Your fellow buddies silently respected you when you showed your new Applet or Servlet.
I slowly forgot HTML.
But now, With new HTML 5.0 killer features, nobody can ignore it. It has the capacity to completely replace these Rich Internet Apps be it Flash, Silverlight etc.
It would soon become a standard and entirely change how we write web applications.
Some of the features are just amazing:
1. Offline storage database
2. Drag and Drop
4. Rich Media tags
& the list goes on..
Check this out:
Demo of HTML5 is in HTML5 How cool is that !!.
And this video on youtube: