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Forum Moderators: phranque
Graphs and numbers would be interesting to some users.
More things for the user to see/do on the website which should keep them there longer.
Users might visit other pages when they see that they get a lot of hits.
Wow factor (the format my stats are in is pretty neat).
Competitors will know where my traffic comes from.
Competitors will know what my top content is and be able to duplicate it.
As far as some kind of implied quality due to popularity, just use hyperbole like 'thousands of visitors a month' or 'the top site in our industry'.
However that would only really be interesting to potential advertisers, so I wouldn't slap it all across the front page. And certainly don't advertise which are your most popular pages, that's just asking for them to be copied by your competitors!