By Brier Dudley,The Seattle Times

LAS VEGAS – After largely missing out on the ballyhooed Web 2.0 that spawned today’s more interactive Web sites, Microsoft roared onto the scene Monday with a set of powerful new tools to build even jazzier sites that should start appearing in late 2006 and beyond.

Chairman Bill Gates and a bevy of executives presented the software and their vision for tomorrow’s Web at an unusual event called Mix06, aimed primarily at the people who design, build and run the world’s top 500 commercial Web sites.

The company simultaneously released a test version of the new Internet Explorer browser – most people’s vehicle to the Web – and apologized for taking so long to produce a new version.

“In a sense, we’re doing a mea culpa, saying we waited too long for a browser release,” Gates said, then pledged to release the next two versions more rapidly.

The heavily technical conference is intended to get Web developers and companies excited about a wave of new products Microsoft plans to release over the next year, including Windows Vista, the updated Internet Explorer and a set of Web development tools.

Yet the conference is also a sort of coming out for Microsoft, a chance to explain how it’s no longer as obsessed with the PC and now embraces the Internet as a platform for software development.

It’s a tricky pitch. Microsoft is trying to embrace trends in Web development that move more computing online, while also telling developers that advanced Web pages will work best on a PC or device running Microsoft software.

“Part of our message here is the Internet’s important – the experience in the Web browser – but don’t underestimate the power of that PC,” said Dean Hachamovitch, general manager of Internet Explorer.

“It’s not like there’s a browser world and a Windows world. It’s “How does the Web get better if I’m running on Windows?”‘

Several developers attending the conference were enthusiastic about the technology, both for Web development and new display technologies in Windows.

“It’s definitely the future, whether you call it Web 2.0 or whatever,” said Loren Heiny, who develops Tablet PC software at Jumping Minds Software in Scottsdale, Ariz.

Web 2.0 is a term applied, primarily by software publisher and pundit Tim O’Reilly, to the post-bubble emergence of the Internet as a platform supporting Web sites that are more interactive, interconnected and service-oriented.

Microsoft brought O’Reilly on stage to interview Gates during his keynote Monday, and the two talked about the company’s strategies and competition.

At one point, O’Reilly drew a grimace from Gates when he referred to Microsoft “cutting off the air supply” of browser pioneer Netscape by distributing Internet Explorer free. The tension released after Gates wisecracked about the historic ‘90s browser war.

“Actually they were giving it away,” Gates said. “There’s a lot of these so-called fights where the other guy really knocked himself out.”

Earlier in Gates’ keynote, companies such as MySpace and the BBC demonstrated how they’re using Microsoft software to build features such as small gadgets that display updated information on a Vista desktop.

The BBC demonstrated how users will be able to search, browse, download and share its video and radio content.

Amazon.com already is using Microsoft tools to let customers subscribe to wish lists, so that they are notified when friends add an item to their list, for instance.

Yahoo! is offering a similar service for subscribing to its music hit list.

Sean Gerety, a developer at TSYS in Atlanta, said he’ll use the Microsoft platform to create a Web application for banks that will enable customers to quickly search through thumbnail images of checks they have written.

In some ways, Microsoft is playing catch-up. Adobe currently makes the leading Web-design and development tools, and there’s a popular set of free, open-source Web technologies known as Ajax.

Microsoft is also adding features to Internet Explorer that have long been in competing browsers such as Firefox and Opera.

Meanwhile, Microsoft is only now releasing test versions of Internet Explorer, Vista and its Atlas Web development platform. Also coming later are Web-design products that will compete with Adobe’s offerings.

And while Vista is expected to go on sale later this year, it may take several years before it’s widely used.

“The real power of that whole platform is based on the Vista operating system, and it’s going to take awhile; I’d say three to five years,” said Richard Monson-Haefel, an analyst at Salt Lake City-based Burton Group and a former Java developer.

At the same time, he said, Microsoft’s easy-to-use programming tools are appealing to Web developers, despite the buzz for alternatives such as open-source software.

“Developers are in the end pragmatists,” he said. “Some of your louder, squeakier wheels tend to be idealists when it comes to what technologies are best, but … everybody else just wants to solve a problem and go home to their kids.”