lucy24 - 4:14 am on Feb 10, 2012 (gmt 0)
In real life, the on-demand preview looks like this:
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/534.51 (KHTML, like Gecko; Google Web Preview) Chrome/12.0.742 Safari/534.51
It must confuse a lot of people that the words in the text don't match up with the image headings. Not the most clear instructions I have seen in a while.
At least it's more honest than when they first introduced Preview. You may remember they showed two versions: "what you see" vs. "what Preview shows". Except that "what you see" was really the Previewbot, while "what Preview sees" was really the googlebot. You could tell because "Preview" (i.e. the googlebot) couldn't get to roboted-out directories. Now at least there's some hint that the previewbot doesn't mess about with robots.txt.