I downloaded the trial version of Sketchup today, and after watching
portions of the tutorials was able to render an end table I am working
on for a client in about 30 minutes. I am sure that it has some short
comings compared to some of the more expensive CAD programs available,
but if what you are interested in is a better rendering of a plan it
works great. I am planning based on this fooling around to start using
it in addition to my hand drawn images for the next couple rounds of
client interactions. Based on my first impressions I might set down the
pencil entirely before too long.

Andrew