Apple will be releasing iOS 4.3 on March 11 along with the iPad 2. The update is compatible with several iOS devices, but marks the end of the line for the iPhone 3G.
The iOS page on Apple’s Web site lists the iPhone 3GS and iPhone 4, third and fourth generation iPod touch, as well as the iPad and iPad 2 as compatible with iOS 4.3. The first generation iPhone and iPod touch were left behind in earlier iOS releases, so it’s no surprise they aren’t listed as iOS 4.3 compatible.
The iPhone 3G supports iOS 4.2 and its minor updates, but can’t take advantage of multitasking like the iPhone 3GS and iPhone 4. As Apple moves forward with new products it often drops support for older devices, so it isn’t too surprising to see the venerable iPhone 3G finally left behind even though it would be nice to see the phone supported up to iOS 5.