Google's SketchUp Pro 6.0 is an enhanced version of its free Google SketchUp 6.0 program. The free version features the application's powerful 3D functionality, while Google SketchUp Pro 6.0 adds two main features necessary for professional modelers.
One is an expanded set of export formats that allow SketchUp modellers to work closely with architects using CAD (computer-aided design) software. The other is the bundled LayOut program (still in beta). You'll need LayOut if you want to print 2D views of a Google SketchUp 3D model (or if you want to project a 2D slide on a computer screen). If, for example, you want to create a set of printed displays for a kiosk, or to present to a client, you need Google SketchUp Pro.
Google recommends SketchUp Pro 6.0 for all kinds of 3D drawing projects, and its available libraries (from Google's 3D Warehouse) include objects for plumbing, interior design, industrial design, and more. Google SketchUp Pro 6.0 is for drawing models, not blueprints - the drawing features don't support the level of precision scaling available in CAD programs, or in Adobe Illustrator, but are sufficiently precise for creating models, mock-ups, and demonstrations.
Once you get comfortable with Google SketchUp Pro 6.0's drawing conventions, you can generate 3D models very quickly. The environment is completely unlike traditional 3D drawing programs, in which you draw and assemble surfaces. Instead, Google SketchUp Pro 6.0 approaches 3D drawing with a design environment based on colour-coded dots, edges, and planes that indicate dimensions. Illustrators who are used to the traditional approach may find Google SketchUp Pro 6.0's interface frustrating at first. But the ease with which you can move a wall, or adjust the pitch of a roof, and interactively adjust an entire project in Google SketchUp Pro 6.0 can justify the learning curve over time.
You can easily apply textures - like brick or concrete - to Google SketchUp Pro 6.0 models, and you can add effects like fog or shadows. You can apply strokes such as pencil lines to give a hand-drawn look to projects. And Google SketchUp Pro 6.0 allows you to add text boxes and callouts to models.
Professional illustrators will probably require more surfacing and lighting features than are available in either version of Google SketchUp 6.0, and will likely turn to plug-ins such as TurboSketch Studio to make models more realistic.
The 3D models you create in Google SketchUp Pro 6.0 also can be used to generate QuickTime movies that allow viewers to move from one perspective to another. You might, for example, create a movie that simulates a drive-through tour of a shopping center. You can find examples of Google SketchUp-generated walk-through movies on YouTube.