It's not much more than just the usual type of generic press statement you'd expect after something like this, but T-Mobile has just issued an official response to the whole Paris Hilton hacked Sidekick "incident":
T-Mobile is investigating the reported disclosure of Paris Hilton's information.
T-Mobile's computer forensics and security team is actively investigating to determine how Ms. Hilton's information was obtained. This includes the possibility that someone had access to one of Ms. Hilton's devices and/or knew her account password.
Given the sensitivity of the situation, and to protect our customers' information, we are not able to provide specific details of the investigation at this point.
Obviously no one seems to know for certain how this all happened, but they've got to be praying right now that it turns out that she accidentally gave someone her password.