Today's Apple's iPhone OS 4 event!

This is the brief version of todays Apple iPhone OS 4 event:

• As of today Apple has sold over 450,000 iPads!

• As of today Apple 600,000 iBooks have been downloaded.

• As of today Apple 3.5 iPad apps have been downloaded.

• Over 4 Billion apps have been downloaded from the Apple app store.

• There are 185,000 apps in the Apple app store.

• There are 3,500 apps in for the iPad in the app store.

• 50 Million iPhones have been sold.

• The iPhone OS version 4 will be released to the public summer 2010.

• Developers may download the iPhone OS 4 preview today.

• The iPhone OS version 4 will feature 1500 new API's.

• The iPhone OS version 4 will offer 100 new user features. Such as Create playlists, 5x digital zoom, tap to focus on video, gift apps, geotagging, places in the photo app, change the home screen, wallpaper, bluetooth keyboards support and spell checker."

• The iPhone OS version 4 will offer Multitasking done in a way that will not suck your battery dry.

• The iPhone OS version 4 will offer: Background audio, Voice over IP (Skype), Background location, Push notifications, Local notifications, Task completion, Fast app switching, Folders, Home screen wallpaper, Unified email inbox, Organized by thread email, Open email attachments, Multiple Exchange accounts, Fast email inbox switching, iBooks for iPhone, better data protection, SSL VPN support, Exchange Server 2010 support, Game Center, iAd Mobile Advertising.

• Apple said that the following sites are using the most current web standards (HTML5, CSS3, JavaScript): CNN, Reuters, New York Times, Viemo, Time, ESPN, Major League Baseball, Netflix, NPR, National Hockey League, The White House, Virgin America, Sports Illustrated, Flickr, People Magazine, TED, Nike, CBS, Spin, National Geographic and will support your iPad or iPhone.

• iPhone OS version 4 for the iPad will be released in the fall.

Read more and see photos from engadgets coverage of Apples event today.