Microsoft has unveiled a suite of Web site design and graphics software that gives .NET developers a set of tools similar to those that have been available for years from Adobe Systems and Macromedia.

As expected, Sparkle Interactive Designer, a new tool for building 3D animation and graphics, is a part of the suite, called Microsoft Expression. Eric Rudder, senior vice president of the Server and Tools division at Microsoft, unveiled a pre-release version of Expression in his keynote at Microsoft's Professional developers Conference (PDC) in Los Angeles.

In addition to Sparkle, Expression includes Acrylic Graphic Designer, a painting and illustration tool, and Quartz Web Designer, a layout and design tool for building Web sites. All of the current names for the individual tools are Microsoft code names.

Microsoft Expression is now available as a Community Technology Preview (CTP), and the suite is expected to ship in 2006. Microsoft plans to make several more CTPs available before a full production version of the suite is released.

While Expression gives designers an alternative to using tools such as Adobe Photoshop, Macromedia Flash and Macromedia Dreamweaver, it's not likely they will begin migrating in droves from those tools to Microsoft Expression anytime soon, said one analyst attending the PDC.

Macromedia's tools are most widely used on Apple Computer's Macintosh hardware, which is still the platform of choice for graphics and Web site designers, said Ron Schmelzer, senior analyst for Zapthink, a research firm in Massachusetts.

"Macromedia and Adobe aren't that threatened because they have a Macintosh installed base," he said. "Most designers prefer the Macintosh [as a platform], and I don't see Microsoft offering Expression for the Mac anytime soon."

Instead, Microsoft Expression fills in a gap in Microsoft's own tools portfolio, he said. Microsoft has not previously had a compelling set of tools for graphics designers, so developers building applications for .NET now will have design tools that are closely integrated with Visual Studio, Microsoft core tool set for building .NET applications.

In fact, by using Expression in conjunction with Visual Studio, developers writing server code can work more seamlessly with designers to create rich user interfaces for .NET applications, Rudder said. Microsoft developers demonstrated this functionality during Rudder's keynote Wednesday morning.

This kind of capability is similar to what Macromedia offers to Java developers with its Macromedia Flex tool, which enables programmers writing server-side Java code to work with GUI (graphical user interface) designers to create rich Internet applications, according to Macromedia.

The San Francisco-based Web tools company recently released Studio 8, a suite of its core design and development tools, including Dreamweaver, Flash Professional and Fireworks.

"We continue to watch all competitive and complementary technologies very closely, including this one," Jim Guerard, vice president of product management and product marketing for Macromedia, said Wednesday of Microsoft Expression.

Adobe is currently in the process of acquiring Macromedia, a deal that was approved by shareholders but is still awaiting regulatory approval.