I wonder if Apple will sue. A new exception was added to the DMCA last year specifically to address things like this:
"Computer programs in the form of firmware that enable wireless telephone handsets to connect to a wireless telephone communication network, when circumvention is accomplished for the sole purpose of lawfully connecting to a wireless telephone communication network."
So it looks like this new law specifically allows you to hack your phone if all you want to do is unlock it. I'm actually kind of hoping that Apple sues the guys who did the unlocking, just to set a precedent when Apple loses.