In his widely read open letter about the alleged shortcomings of Adobe's Flash technology on the iPhone, Apple CEO Steve Jobs wrote, "Most Flash Web sites will need to be rewritten to support touch-based devices. If developers need to rewrite their Flash Web sites, why not use modern technologies like HTML5, CSS and JavaScript?"

Scribd, the social document sharing Web site, has done just that.

At the Web 2.0 Expo in San Francisco on Thursday, Scribd CTO Jared Friedman announced that his company has decided to abandon its three-year-old use of Flash in favor of HTML5.

"After three years of building on Flash, Scribd is starting over and building everything on HTML5," declared Friedman.

Flash, he said, is terrific in a lot of ways, but has the drawback of wrapping content in a separate application. As a result, Scribd's Flash document reader ended up duplicating many browser functions, which took a lot of work and resulted in a poor user experience, he said.

"Why do you need a special reading application just to view a document?" asked Friedman.

As Friedman demonstrated on an Apple iPad, visually sophisticated document can be rendered using HTML5 just fine, mostly.

It hasn't always been this way. While browsers are widely used for reading Web pages, it has only been recently, as modern browsers have implemented HTML5 support, that the typographic and layout shortcomings of browsers have become less of an issue.

Flash still has advantages: Flash content remains more consistent across platforms and devices, and doesn't betray its coding the way that JavaScript does.

But perhaps most significantly, Flash is still ahead in terms of authoring tools. There isn't yet an HTML5 authoring and programming environment that's comparable to Adobe Flash or InDesign.

Something of the sort is coming -- Adobe CTO Kevin Lynch promised as much, and others are surely working to beat Adobe to market -- but it's not there yet.

Our editors take Apple's new platform through its paces, in the office and on the road. Here are their (differing) assessments of what works well and what doesn't. Download the report here (registration required).