[m0nastic]

Based on some completely suspect math, having 1000 engineers available for the length of the conference "costs" apple ~40 million dollars in productivity:

num_engineers * total_session_hours * (revenue_per_emp / 2000)

where num_engineers = 1000, total_session_hours = 40, and revenue_per_emp = 2020000‡

‡ http://www.wolframalpha.com/input/?i=apple%20revenue%20per%2...

[switch007]

Good point. Still, the $7m is a minor dent in the overall cost, so it seems almost insignificant.

[m0nastic]

I'd be almost willing to bet that because the cost is so insignificant to them, the WWDC ticket price is almost entirely meant to set a bar for the types of developers that Apple wants to attend the conference. Specifically, professional developers who make money from the Apple ecosystem, to which the ticket price is a pretty insignificant expenditure for the hopeful value that they recieve from being there.