It seems like much of the time, when something old is well done already, someone comes along and makes it new. Sketchup, at a preliminary glance is what one would use instead of CAD. It allows you to build and create 3D objects fairly easily and intuitively, as if you were manipulating it in space with your hands.
It recently got aquired by Google. So speculation is amok as to what this means for Google's overall strategy. Personally, I think Google is big enough, like Microsoft, and Sun, to have their hands in everything. However, they seem to have a better track record than Sun so far when it comes to making their products work well as a thematic and cohesive whole.
The previous aquisitions that haven't yet made a showing on Googles' product lists are the things related to real-world computing. Things such as mobile socialization and traffic information haven't yet surfaced. In addition, a friend of mine was approached by Google for a job in haptics (force feedback in robotic surgery). When looking at their job listings briefly, they do also invest in bioengineering and chemical fields.
What will Google use SketchUp for? No one knows. But I know this: that the easier people can create information--whether it's written word, images, sounds, etc--the more that type of information is going to proliferate. If it's really easy to post entries to a blog, many blogs will spring up. If it's really easy to take photos, many photo sharing sites will spring up. If it's really easy to make 3D objects with SketchUp, the more object manufacturing sites will spring up. Thus positioned, Google can continue to offer services which filter and organize that information; and that will contribute to this advertising revenue. But now, it seems to be in the position to also encourage people to create that information.