Tuesday is the day breathless iPhone 5 watchers have been waiting for.

Apple is expected to spill the details of the next generation of iPhone and its new mobile operating software, the iOS 5, at headquartes in Cupertino, Calif., within hours

The "Let's Talk iPhone" tagged message in Apple's invitation stoked the media frenzy. A common prediction for the iPhone 5 is a tear-shaped design. But many are doubtful, saying such a design would be inappropriate for landscape orientation, used in gaming.

Another theory is that Apple will only release iPhone 4S, an iPhone 4 with upgraded features. This is supported by some evidence such as a photo from a Brazil factory and iTunes beta code that is matched to iPhone 4S.

That would disappoint Apple consumers waiting for an iPhone 5.

Besides speculation on the design, there will be definite advantages to the iPhone 5 features and specs. It is expected that new iPhone will have A5 dual-core processor, which is currently found on the iPad 2, as well as 1GB RAM and an 8-megapixel higher-resolution camera.

The iOS 5 will include improvements on the Mail and Safari, a notification center similar to Android's, Twitter integration and iMessage, an instant messaging platform for iOS devices.

The new iCloud is also integrated in iOS 5, so one can re-download purchased music, apps or books to any of your devices or computer, while the master copy resides with Apple.