AirDisk might also be the issue...
Hi All,
I'm experiencing the same behavior on my brand new iMac 27 running OSX 10.6.2. I used to have a USB HDD connected directly to the iMac and used it for Time Machine Backups. I got an Airport Extreme Base Station and moved the disk and made it an AirDisk. Now my iMac seems to hang with a blue screen for minutes before displaying the Login Box. My MacBook is also using the AirDisk, but is not having problems.