Apple's new Thunderbolt Display is kind of like when the Power Rangers upgraded to Thunderzords from Dinozords—they're still just Zords (er, a display), but now with more Thunder-y power. Er, right.
What's that mean? Well, if you recall, Thunderbolt is the new interface that's got 10Gbps of throughput in each direction. So, you can daisy-chain a bunch of Thunderbolt displays (or other peripherals) together. Or more practically, leave a hard drive or other Thunderbolt peripheral perpetually plugged into your Thunderbolt display. Then when you connect your computer via Thunderbolt, you're all ready to go. No cable pulling and plugging and re-plugging. And all your data transfers are superfast.
Of note, the new Thunderbolt Displays don't appear to have a USB cable at the end of their connector tail—so if you wanna use the FireWire and USB ports on the display to connect peripherals to your Mac, it looks like you'll have to use a Thunderbolt-enabled Mac in the first place. On the other hand, it's terribly convenient if you do—one tiny connector is a single gateway for three USB ports, a FireWire port and an Ethernet port.
Other notable upgrades: The built-in webcam's been updated to a FaceTime HD camera. It's still $1000, just like before. [Apple]