With that amount of traffic I'd expect a lot more revenue. 1.) Clickbank affiliate links (dont forget to cloak) 2.) Registration - Give away something valueble for free to get their email address, then continue to send them valuable stuff and mix in affiliate link offers 3.) Hire someone to work on your SEO
Have you tried adsense? You could swap a few ads for a week at least to see if your earnings improve. You could also contact more sites, as with more advertising choices you could negotiate for a higher ads space price.
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