I do not come to Hacker News, however, to waste time. I come to Hacker News for intellectual debate and a deeper form of thinking. Both of these, among others, foster personal growth and learning. That is the value I pull from Hacker News. I'm sure PG would understand where I'm coming from here. So let's keep "anything interesting" to digg. They're doing great so far.
What to Submit
On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity.
> Please don't submit comments complaining that a submission is inappropriate for the site. If you think something is spam or offtopic, flag it by going to its page and clicking on the "flag" link. (Not all users will see this; there is a karma threshold.) If you flag something, please don't also comment that you did.
I found it mildly interesting, not interesting enough to upvote, but a bit - it had a tip on an interesting piece of software too (Tracker Video analysis). Obviously other people found it a bit more interesting, there's nothing wrong with that.
The title is a bit cheating though, since I thought it was about actual birds, not a game.