Update: Today, Apple release iPhone 4.0 OS for the 3GS and 3G and the soon-to-come iPhone 4. If you want more details than below, here’s a great link to the major changes of iPhone 4.0 OS.

Today Apple announced the much anticipated iPhone 4.0 OS, coming out to an iPhone 3G/3GS or iPod Touch near you late this summer. The iPad will get the iPhone 4.0OS update later this fall, which kinda sucks.

But there’s a lot of good news – here are the top changes (there are 100 in total) to the new iPhone software:

UPDATE (MORE PICS FROM A FRIEND OF MINE AT BOTTOM OF PAGE!)

(1) Multitasking – FINALLY! We will have the ability to run several apps at once – example: play your favorite music on Pandora, then open Tweetie and twitter away, then go to Facebook and update your status all while allowing these apps to run in the background in a very cool way. There are 7 major new technologies that will allow the iPhone 3GS and iPad to multitask in ways no other phone has before (source: TechCrunch)

-Background audio: i.e. Pandora can play in the background and popup controls can control it.
-Background VoIP: Skype calls will continue if you need to switch apps; a “return to call” button will show, and you can also receive Skype calls on a locked phone.
-Background location: turn-by-turn directions can continue when you leave the app. Music can run at the same time and will quiet down when directions need to be said. Very slick. Uses cell-tower-enhanced AGPS. A notification will show in the status bar if an app is transmitting your location. You can also turn off location app-by-app.
-Push notifications: the same push notifications you know and love.
-Local notifications: in-phone notifications for, say, pop-up alarms and such. Local app stuff.
-Fast app switching: this is the service by which apps can store their state when you switch to and from them.

(2) The iPhone will no longer have clutter thanks to Folders, the ability to put many similar apps into one stackable folder, which is very cool. This feature is very similar to the stackable folders we see on Snow Leopard or OS X.

(3) There will also be ONE, unified mailbox – it will use all of your email accounts and put them into one mailbox allowing you to not have to go back and forth from your Yahoo email to your MobileMe email to your Gmail.

(4, 5, 6) The last 3 big changes deal with iBooks (the iPad has great iBooks and now the iPhone will have them, too!), a completely live, socially active Games Center (allows you to play games online with friends and challenge them to duels plus much more) and last but not least, iAds. This is a way for developers to make money by placing really innovative and cool ads into apps. Steve Jobs explained iAds by showing us the following:

-Apple will sell and host the ads; the revenue will be split 60/40, with devs getting the 60. Anybody can make them, just like apps.
-Ads are done in HTML5 (a little dig in there for Adobe)
-Fully interactive; the Toy Story ad Steve showed looks like a native app, includes a game, graphical interface and everything. They can call out for showing times, current prices, and so on. It’s essentially a commercial break app.
-Access to APIs: somewhat scarily, ads will have access to location, accelerometer, and a lot of other stuff.

Please note: this new iPhone OS will come out this summer to the iPod Touch and the iPhone 3GS. An update will work for the iPhone and lower gen iPod Touches, but will NOT have multitasking.

A good fan of the Moxie Mo Show (Lionel Archuleta) has the new iPhone 4.0 OS and showed me some amazing screen shots, never seen before. This shows you how your camera will zoom while taking pictures and video:

For more information, stay tuned to the Moxie Mo Show.