iPhone 4S begins shipping today, and with suppliers running out and record numbers being sold, iPhone 4S will be tough to nudge out of the top smartphone slot. iPhone 4S' best feature could be the voice recognition technology known as Siri because it's supposed to be able to understand you well enough to create text messages and emails and even read them back to you.

This type of speech-to-text software has been tried in many places before but Apple seems to think they have found the right formula for it this time. Apple's version is based on technology they bought up in 2010 from a company called Siri. Before Apple even made that purchase, Siri had launched its own app, which until last week was available in the app store. Apple has now pulled the app, having integrated it into the Siri feature in iPhone 4S. Additionally, iPhone 4S comes with Apple's most advanced mobile operating system, iOS 5, which comes with over 200 new features.

The settings and setup and the app tweaks and iCloud optimized features means iOS 5 makes using an iOS-device even easier. Furthermore, iOS 5 will be compatible with the iPod Touch, iPad, iPad 2, iPhone 3GS and iPhone 4. Apple could ultimately be going for an integrated OS that works for mobile and desktops, and that would compete more with Android's new Ice Cream Sandwich. But until then, iOS 5 could rule the mobile OS world despite the setbacks it experienced the day it was made available to other iOS devices. Initial launch hiccups aside, iOS 5 introduces cloud based storage, full Twitter integration, Wi-Fi syncing and a new messaging system that Android devices will be aiming at for some time.

Android Ice Cream Sandwich will possibly launch on Oct. 19, so then we'll know if it matches up with iOS 5. But, it's hard to imagine Android launching anything like Siri. The buildup of hype before the iPhone 4S launch may have been worrying to some of Apple's rivals, and iPhone is still the defining smartphone out there, but those rivals shouldn't be afraid because the smartphone war is here to stay. There will be plenty of chances to take iPhone 4S down a peg, starting with the Oct. 19 Ice Cream Sandwich launch.

Let us know in the comments if you are looking forward to Oct. 19 or if you've got iOS 5 and are busy playing with all the new features.