Why would you take the chance on .net or .org? Because it is easier for you to get a name or because it is easier for a user to remember and browse to it.
they have the money to pay a couple hundred k for a domain. but it was after the fact, not before.
that being said. having the .com is a very smart move.
Disclaimer: My startup went for a non-.com name: tipit.to
I probably would not consider a .org.
Is the comparison more like A or B below?
A.
myphotos.net
mycoolphotos.com
B.
photos.net
thephotositookatthebarlastnight.com
For example, I've mentioned justin DOT tv to several people, and they still try to go to justintv.com .