buckworks - 1:48 pm on Jun 28, 2010 (gmt 0)
Within AdWords the default is no cap on impressions.
Advertisers can set their own caps, though, and in many cases I think it would be wise to do so.
a person needs to see a message 6 or 7 or whatever number of times
I don't think many folks would complain about seeing the same ad 6 or 7 times in a few days.
But to see the same ad 66 or 77 times a day, that just gets stupid.