This means that you get a ton of portable storage space, and you still don't need an AC adapter. You just plug the drive into a USB 2.0 port and proceed with your business. Simple, easy, nice. Pricing and availability is still up in the air for now, but we'll keep our eyes peeled. [Seagate]
Right now, the highest capacity for the 500GB triple interface OWC Mercury externals is $164 and $239 for 5,400 and 7,200 RPM respectively, and $119 and $189 for the USB 2.0 alone. I wonder how close Seagate's offering will weigh in on price with the 140GB gain in capacity.