ios 4 announce 260x172 iOS4 Now Available for Download!As promised, Apple has released iOS4, you should find it immediately available via software update in iTunes. If not, you can download the update direct here (thanks to Mac Stories):

This is a free update but only works with specific iPhone models:  iPhone 3G with no multitasking, iPhone 3GS, iPhone 4 and 2nd / 3rd generation iPod Touches.