chichipucca
Did anyone receive a reply from the interviewer?
If he writes back, does it mean he feels bad about the perspective and tries to be nice?
If you had sent a thank-you note over email, then, I think it is a nice gesture by the interviewer to send back a brief response to it. Nothing unusual.
On the other hand, if you had not initiated a thank-you note, and there was nothing in your application (including the interview) that requires your special attention (sending missing material etc.), it sounds a little unusual that the interviewer sent you an email out of the blue.
But the verdict would really depends on the actual content of the email you received. If it felt weird to you, you are probably right, since you know the situation best.