When the iPhone first launched, Jailbreaking was the only way to get Apps on Apple's closed system as well as features like tethering, recording video, copy and paste and MMS. With the advent of the App Store, 3rd party Apple endorsed apps and the iPhone 3G the reasons for Jailbreaking your phone are alot less. That said Apple's approval process for the App Store is stringent bordering on crazy and there have been times, when good apps from valid companies have been rejected or pulled from iTunes and the App Store..case in point the original Sling Player, which is now available through the App Store...The Google Voice app, and so on.
If you're interested in pushing outside Apple's box jailbreaking might be for you, but be aware that doing so voids your warranty, and if you need to take the device in for warranty be sure to return it to the stock OS first.
If you're interested in pushing outside Apple's box jailbreaking might be for you, but be aware that doing so voids your warranty, and if you need to take the device in for warranty be sure to return it to the stock OS first.