And Penny Arcade's is likely spot on, actually. I thought the numbers odd at first too, since I get roughly 1000-1500 unique visitors per day. Then I remembered this is the number of unique visitors per month. If you visit Penny Arcade's site every day you don't get counted 30 times by the metric. You get counted once. So Penny Arcade doesn't have 249,999 unique visitors per month. It has roughly 249,999 readers who regularly visit their page. Quarter of a million ain't bad.
I dunno. Khoo's "webcomic business model" graphic says "over 1,000,000" readers per month. Now, granted, "readers" is vague, but it would seem to *me* that 1,000,000 would be too low for simply a count of total "page views". Furthermore, if we consider a month to be the "term" for considering uniqueness, ~250,000 unique viewers with ~1,000,000 "page views" (if we suspect "readers" means "individual views") would only be about 4 views per visitor for the whole month. To me, that seems unlikely, as well. I *suspect* that, ignoring the PA forums, 250k unique visitors per month is low (especially given that Khoo states the revenue for PA is north of $500k/yr, and given what we know of their operations and staff, that seems plausible).
Of course, that's revenue, not profit. As such, one could argue that large expenditures like PAX could result in the stated revenue figure being deceptive. It seems, though, that the state of their organization is robust, and so I think we can assume that their margins are rather healthy. But if we're generous and say that PAX is responsible for 25% of revenues for the past fiscal year, that's 75% that had to be made up through advertisement and merchandise sales.
Now, it's fairly commonly accepted that most viewers of any comic don't buy anything related to the franchise. maybe 1% of the total. *maybe*.
So let's do some simple estimating, 75% of 500k is $375k (Khoo just says "more than", so eh, we'll go with the minimum).
If we need just merchandise (figures, books, posters, etc) to achieve that $375k, and assume that only 1% of 1,000,000 readers buy something in a year at ~$14 (let's throw a number as an average for the moment) that'd be 10,000 transactions
So:
$375,000/14 = ~26,785 transactions
What if we give the $500k some more subdivisions and say that 25% of that $500k is also advertising, that'd be $250k that needs to be made up by merchandise sales:
250,000/14 = ~17,857 transactions
How about 50% if the $500k in revenue per year is advertising?
125,000/14 = ~8928 transactions, a bit lower than the 10k. Personally, I highly doubt they make 50% of revenue from advertising.
So, we need to have half of PA's revenue (with PAX being 25%) to be from advertising before we get down to the 1% of a million per month readers that you could generously expect to buy merchandise.
I suspect, though, that less than 1% of their viewers buy anything from them. If we assume .5% buy merch from them, you need more total viewers to make it to those same numbers.
In short, I don't think 1,000,000 unique views per month is at all unreasonable.
Web stats shouldn't be so hard to pin down. Has always bugged me.