Worrying news from MacFixit:

What's going on here?"dmnotifyd" apparently sending Apple user information
Several users have reported that an application called "dnotifyd" is sending system information back to Apple.
Jim Czech writes:
"Since my upgrade last night to Tiger, I have noticed something going on in the background. This was never observed in the past, but thanks to Little Snitch I 'caught' this one.
"This particular app is attempting to contact 'configuration.apple.com' every few minutes. I don't have a packet sniffer, but am curious just exactly why Apple needs to 'check my configuration' every few minutes.
"After the upgrade, I started testing all my apps, one by one, to see if there were any compatibility issues making the move from 10.3.9 to Tiger. When I applied the Little Snitch update, I then noticed this "dmnotifyd" app was phoning home. I thought it was possibly related to running each app and then Apple was gathering stats for compatibility, etc.
"However, even with no applications running, 'dmnotifyd' is still contacting Apple.
"I have allowed several requests (since I have nothing to hide) thinking it would stop. It doesn't matter whether the request to send is allowed or denied, it runs non-stop."