It's making a bit over $1,000 in monthly ad revenue. Traffic is at ~3k dailies.
I did this as a weekend project 2 years ago, and at some point migrated my blog to it to pick up DomainRank. Other than that I've mostly left it alone.
My project is: http://sudokuisland.com
How would you go about it? Thanks.
My plan is to improve the PageRank and DomainRank, and eventually to make the product better (since Google presumably picks up on that through bounce rates, time on site, sharing). So that'd be the general strategy I recommend.
Another metric you can optimize is the number of times a first-time visitor returns, because it acts as a multiplier on your traffic. Say you get 100 organic first-time visitors per day, if each visitor returns 5 times, you'll have 600 total visits per day.