I serve banner ids from one of my domains and there are times when the ads don't show on another of my sites. Then I realize that my serving domain is "down". Maybe 2-5 minutes per day. It's just a guess and could be less often than 1 period like that per day.
It would be good if there were some official objective stats we could all review - it would only Dreamhost as I suspect a high % of people complain have caused their own problems.
Also you probably hear less from the people who are not down, so the perception can get skewed.
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