Having the ability to natively share an internet connection from mobile to other personal devices for free is definitely a beneficial feature that comes in handy at differing times. However, as handy as the feature is, some users often find themselves infuriated when they realize that their carriers have either disabled the feature or want to charge a premium on top of their current plan to use it.
According to a report by AppleInsider, AT&T has provisioned the use of Personal Hotspot feature to a developer running iOS 4.3 Beta.