People who can create an attractive UI (like a designer) and write code (like a software developer) are getting called various names... a lot of new names, like dev-igner, des-eloper, design-loper, designer-developer, creative developer, or integrator.  My favorite is "devigner." 

A devigner is someone who can work on both sides of the designer-developer workflow. Devigners have been described by Adam Kinney as people who design and develop, by Ryan Stewart as people who move seamlessly between their development tools and their design tools, by Heather Solomon as people who can bang out CSS and pretty graphics and turn around and fix the UI in C# code, can do up a fine front end, but actually understand the backend, and by Kevin Tate as someone how is in-between a 'designer' and a 'developer,' a design/developer hybrid.  Fernando Comet even declared the 5 Commandments of a Devigner.  

Here is my list that defines the skills needed to call yourself a well rounded devigner:

• Emphasizes the user experience (UX)
• Can create UI code
  • Uses "developer" or "designer" tools
  • Makes CSS, HTML, XAML, Flash, etc.
• Can create backend code
  • Uses "developer" tools
  • Makes UI logic, business rules, database and web service interaction, etc.
• Can create artistic graphic designs and has a good "design sense"
  • Uses "designer" tools
  • Makes bitmap graphics, vector graphics, etc.

In other words, a devigner is someone who is is skilled in UX, UI, software engineering and graphic design. 

How do you become a devigner?  Get training & experience in those four areas. 

What am I doing to become a well rounded devigner?

• I've emphasized usability for years (i.e. Don't Make Me Think)... DONE
• I've worked on UIs for years (both windows and web, now WPF and Silverlight)... DONE
• My primary skillset is software development with Microsoft technologies (MCSD + MCDBA)... DONE
• I've dabbled a little with Photoshop, GIMP, Paint.NET, Fireworks... FOCUS HERE!

To round out my devigner portfolio of skills, I am enhancing my design skills, specifically with the Expression suite of "designer" tools.  Expect to see some posts about them! 

With the industry's current emphasis on designer-developer workflow, there will be demand for devigners who focus on building good UX and are competent with both developer tools, like Visual Studio, and designer tools, like Expression Studio.