For the most part the Dingoo A330 specs are identical to the Dingoo A320. The main differences in this new model are the amount of RAM, and the addition of a 2.4ghz wireless controller receiver. The specs follow:

CPU: 400MHz Jz4740 Revised Processor and Motherboard
RAM: 64MB
Storage Capacity: 4GB
Display: TFT 2.8" QVGA LCD, 320x240
Battery: 1700MAh Lithium ion battery
Dimensions: 132×57×15 (length x width x height, in mm)
Weight: 120g
Internal 2.4GHz Receiver Module, supports 2.4GHz wireless controller

The LCD screen seems more colourful, and is definitely an improvement over the one found in the Dingoo A320. The Dingoo A330 is using the same IL9331 LCD Controller as found in newer versions of the Dingoo A320.
The Dingoo A330 has a near identical IO/button layout to the Dingoo A320, with some nice differences. These can mostly be seen as enhancements: 

Speakers moved to back of unit
Shoulder buttons easier to press, more like psp triggers than buttons
Buttons on unit are now clear plastic with labels on underside
Features a wrist-strap loop, which is something the a320 missed
The usb port is now a standard mini-usb connection, so the usb cable fits better than with the a320

The Dingoo A330 is pretty much the same size as the Dingoo A320. The left/right edges are now curved so that they fit more ergonomically into your hands, and the back side of each end is slightly thicker, again adding to the ergonomics. 
Unlike the Dingoo A320, the plastic "nubs" covering the screw holes on the back of the unit seem quite firmly secured