Will this hold my 63 pound black beauty??!!

I would be afraid to buy based on pictures. What if it doesn't turn out to be as ugly in real life? Then what?

Also I'm not too sure about those wheels. And the glass. Other than that.... you could probably throw the glass away, fill the whole thing with sand, get a few cutting boards, and some BDR Cones, and with just an extra hundred bucks or so have a pretty decent rack. 

I know they would up here, not sure about down under. No, really, I have two Primaluna Dialogue 7 monoblock's that do fine on tempered glass.

You could also consider your local glazier for custom thicker glass. 

I wouldn't take the chance. I'd put the amp on an amp stand and keep it on the floor.

there are two load characteristics which may be of interest

load point capacity  - how much weight a floor will hold per unit area.  The common example is the displacement of a woman in high heels.
At some measure the weight at  the point of the heals and soles will crush thru.  generaly in pounds per sq. inch

floor load capacity - how much total weight that glass and it's support  mechanism hold before crashing down

you might test the later by stacking workout weights or 10 gallons of water