I now have a top on the table. I used 3/4 birch plywood for the top.
The shelves are 11/64 inch plywood. The lower shelves are reenforced with 2x4 material spanning the space underneath, while the upper shelves are reenforced with 3/4 birch ply under the front and back, and from above on the sides, where the supports also serve as low sidewalls to keep things where they are intended to be kept.
I finally have a permanent home for my drill press. I'll move the support arm for the vacuum attachment in a day or two, and I'll be done with that. I'll also be routing a slight chamfer onto the edge of the table this week. The table sits at the same height as my table saw, so the chamfer will be of some benefit when I'm ripping long stock and need to use the table as outfeed support.
The first thing I'll be doing tomorrow is cleaning up and moving a few things out of my shop... like the display unit that looks like a ladder. Those weathered boards standing up on the table top are the shelves that bridge the rungs of the ladder. These pieces will have a very nice, comfortable home right next door in our cozy little storage building.
Next I'll build the drawers in the center section, but I'll have to wait a while to get started because I have a couple of other projects which must be completed first.