By this time tomorrow, we should have a pretty good idea about what the new iPhone OS will look and feel like. The rumours are flying all over the place, but let's address two of the most commonly reported upcoming features.

First is multitasking. By far the most talked-about and most-desired of the rumoured features, Apple is reportedly preparing to allow iPhone users to run multiple applications on the device at once. This is actually something that the iPhone has been able to do for some time. If you were to jailbreak your iPhone and accept the risks that come with that, you can already run two or more applications at once.

But Apple has until now not allowed it. Some have suggested that the reason for this is security. When you limit activity to one application at a time, it's pretty much impossible for a malicious program to run in the background without the user knowing. Also cited was battery life. Running multiple apps means more work for the antenna, memory and processor, meaning more drain on the battery. Additionally, the wireless carriers were likely less than thrilled with the idea of even more traffic while they were still building up their networks to accommodate the iPhone.

The second rumoured new feature is something that users will be less enthused about, but developers might perk up over; an ad network. Earlier this year, Apple purchased mobile ad vendor Quattro Wireless. Now the word is that the acquired firm will be turned into an advertising platform for the iPhone OS that developers can use within their Apps.

Interestingly, this might also be good news for Apple's newest rival in the smartphone space. Google is facing anti-trust accusations over its attempt to buy another mobile ad platform in AdMob. If Apple can launch an add service, Google hopes to use it as evidence in its case.