Tuesday, October 4, 2011 at 2:13 am.

Why today’s iPhone event is so important for Apple

It’s not just a new iPhone: It’s a new product lineup for Apple’s most important business unit, going into its most important period of the year.

Last quarter, Apple’s iPhone business generated almost half of its total revenue, and 60% of its year-over-year sales growth. This holiday season, Apple could ship 25 million iPhones in a quarter for its first time ever.

Chart: Apple's iPhone business in context

Related: Don’t be disappointed if Apple doesn’t announce an “iPhone 5” today