The iPhone 2.0 Software update was available unofficially today and Gizmodo reports that hackers at the iPhone Dev Team already have unlocked and jailbroken the iPhone 2.0 update. A couple weeks ago we actually reported that unlocking the 3G iPhone would be harder - looks like it is not that hard afterall.

Their iPhone unlocking tool Pwnage is not released yet, so it is hard to say if unlocking will actually work on iPhone 3G devices or if it just will apply to upgraded iPhones. This time around it will be harder though to buy a new iPhone without signing a contract as carriers require you to sign a contract at purchase.
It will also have to be seen how attractive unlocking of the iPhone 3G will be to iPhone owners. It could add some flexibility on using more SIM cards and install apps outside of the App Store, but this also could lead to lots of hassle.
More details on Gizmodo.