At an event at Apple headquarters in Cupertino, CA, today, Steve Jobs announced new iPhone features that will allow it to play nicely with Microsoft Exchange and ActiveSync, the e-mail, calendar, and syncing software used by many businesses. The iPhone will also work with AIM, AOL’s popular (and much requested) instant-messaging software, and a handful of games that take advantage of the built-in accelerometer. In addition, the company released a software kit that lets developers make their own programs for the phone, sold through Apple’s App store, which can be accessed via an iPhone or iPod Touch. (Blogs Engadget, Techcrunch, and Gizmodo posted live updates from the event.)

The announcement opens up the iPhone to developers, appealing to independent coders who have already been writing programs, without Apple support, for the handheld. (See “The Next Generation of iPhone Hacks.”) But with the release of the software development kit, Apple is adding legitimacy to these programs and making it easier for iPhone users to download and run them. The kit was released today, and consumers can take advantage of third-party software when the iPhone software is updated in June.

But the biggest news is for the business world. Since the iPhone was released last June, businesses have been excited to integrate the phone into their IT infrastructure, as many currently do with Palm Pilots and BlackBerrys, but the lack of Apple support has made it impractical. In addition to offering support for Microsoft Exchange and ActiveSync, iPhones will be able to virtually, and securely, access a company’s internal network. And as a security measure, it will be possible to remotely erase data from lost or stolen phones.