The Sixaxis motion-sensing feature is still present and accounted for along with the familiar Bluetooth wireless connectivity. Unfortunately, the DualShock 3 retains the annoyances of its predecessor. Chief among them: the built-in lithium-ion rechargeable battery isn't removable, so when it eventually dies (admittedly, probably several years down the road), you'll have to buy a completely new controller. (By contrast, the Xbox 360 and Nintendo Wii have user-replaceable battery packs.)
The other major gripe with the DualShock 3 is the $55 price tag. That's anywhere from a $5 to $15 premium over the street price of Xbox 360 and Wii controllers, as well as the existing Sixaxis PS3 controller (which will be discontinued now that the DualShock 3 is available). To add insult to injury, Sony doesn't even throw in a USB cable for recharging.
If you haven't yet taken the PlayStation plunge, you might want to wait until June, when Sony will be releasing a new PS3 bundle for $499. It will include an 80GB console, the DualShock 3 controller, and the long-awaited Metal Gear Solid 4 game. By our math, that means you'll be saving a few bucks over buying those items separately. (Presumably, other PS3 bundles will eventually begin packing the DualShock 3 in place of the rumbleless Sixaxis controller later this year.)
Comparison shoppers should also note that Nyko makes the Zero, a wireless PS3 controller with rumble that costs about $50. While you might save a few bucks on that model--and, notably, it does include a USB cable and detachable battery--it's tough to recommend it over the familiar design of the Sony DualShock 3. We just hope the price of the Sony model drops closer to $40 with time.