Apple starting selling tickets for its Worldwide Developers conference earlier today and its already sold out.

[ad#Google Adsense 300×250 in story]A note on Apple’s developers page where the “Buy Now” button used to be indicates the conference sold out. That should be around 5,000 developer tickets sold since this morning.

Apple said this year is going to be about iOS and Mac OS. “If you are an iOS or Mac OS X software developer, this is the event that you do not want to miss,” said Philip Schiller, Apple’s senior vice president of Worldwide Product Marketing.

The Loop reported earlier today that there would be no iPhone, iPad or Mac hardware at this year’s event. Instead, Apple will focus on its software platforms.