The press conference the world has been anticipating for months finally kicked off on Wednesday, and Apple (AAPL) didn’t waste any time getting the show on the road. Tim Cook took the stage at the Yerba Buena center in San Francisco and started with some numbers. After announcing that OS X Mountain Lion has been purchased more than 7 million times to date, the Apple chief noted that his company has sold more than 84 million iPad tablets and more than 400 million total iOS devices to date. Cook also noted that Apple is responsible for 68% of all tablets shipped in 2011 and 91% of all Web traffic from tablets, suggesting that sell-through among Apple’s competitors has not been anything close to what Apple has seen with its iPad. Cook went on to confirm that there are now more than 250,000 apps tailored to the iPad in the iOS App Store, and iPad users download more than 100 apps each on average.