I am not sure why... But at first, when I was looking at this drive for the first time, I got impression that is it regular 7200 drive (since same drive with 3TB is 7200RPM). RPM or warranty information are not clear presented on newegg or amazon. But then I started to look up more information on this and found that is it 5900RPM disk and that Seagate is trying to cover this information up.
Even on Amazon it has wrong information:
http://www.amazon.com/Seagate-Deskto...ds=seagate+4tb4TB storage capacity with SATA 6Gb/s NCQ Interface
Double your capacity and drive down costs with up to 1TB-per-disk hard drive technology
Seagate AcuTrac servo technology delivers dependable performance, even with hard drive track widths of only 75 nanometers
Free Seagate DiskWizard software allows you to install 3TB and 4TB hard drives in Windows, including XP, without UEFI BIOS
7200rpm Spindle Speed
There is whole topic on this on Xbit forum. http://forum.xbitlabs.com/viewtopic.php?t=20232