In some scenes of this episode, Data has blue eyes. It's a small change, but it was very disconcerting. A "Trek Snafus" page has this as the explanation: Is this a known Trek fact? I just can't believe he could forget his contacts or that the director could miss that fact. I assume it was a very subtle (well, not so subtle, since it leaped out of the screen at me) attempt to show Data as he existed in an alternate universe.