The game he's writing about produced average revenue of around $4500 a month for it's first two years, and is currently making around $1000 a month. That's not enough data to plot a curve, but his long term revenue for a game seems quite respectable, particularly when considering he has a stable of 12+ games that are probably all still earning some amount.
For me, this was not as interesting as Part One from a business/startup standpoint, as there wasn't much more detail. But my inner "game creator" is always excited to see a small player succeeding in this crowded arena. We should all be so lucky to earn a living doing what we love - and not get sick of it after all this time.
If you haven't played the "Exile" games, you should (if you can get them to work on modern systems). They're very non-linear and a lot of fun. I remember when I first bought these games in middle school.
