Further to sketch up pro 6, the Google Sketchup 7 has released! You can take a look at What's New in 7 page and also download for free available for Windows XP/Vista and Mac OS X (10.4+).
There are some special new features that I would like to highlight in Sketchup 7 are as below,
You can draw a free-line polyline to create a irregular shape of form, you can even edit the line with a path edit command.
Beside polyline, there are no more stretching and distortion when you Scaling an object.
Here are some videos of Sketchup 7 demonstrating the new feature in SketchUp 7 version.
Official Google Blog: Introducing SketchUp 7