The biggest change is that the frame is designed around the claw, rather than the claw being a later addition.
The claw's anchor point is at the bottom rear, and there's an opening at the top front of the frame to allow the claw to lift up to about 70 degrees from horizontal.
The wheel gearing is entirely internal, and the motors are in the same plane as the wheels, freeing up more space above.
For balance, two casters are mounted at the back of the frame. Unfortunately, the center of gravity of the robot is almost directly over the drive wheels (despite the weight brick mounted on the back), causing it to tip forward briefly when it reverses.
The wheel gearing is entirely internal, and the motors are in the same plane as the wheels, freeing up more space above.
This incorrectly-focused picture over the left wheel might be good for a desktop picture (that's "wallpaper" to you Windows types).
Here you can see all the wheels, the drive motors, and the 4x10 plate which provides a lower limit for the claw.
The pneumatic cylinder at the top of the picture lifts the claw up.
The claw gripping an object. Here you can see the 1x4 tiles the claw rests on in its down position.
Left side of the Megabot; you can see just how high the claw lifts.
Here's the compressor motor, battery box, pressure switch, and air tank.
This version of the Megabot incorporates my new compact dual-pump compressor, of which there will be more pictures up sometime.
The RCX removed to reveal the drive motor gearing.