My best guess from the photo is that' s around 40 bf. Could be way wrong, but looks like a pile about 1.5 high by 3'wide by 8' long to me. If my guess is even close, then less then $2/bd.ft. Looks as though its surfaced with decent edges so I'm thinking its a good deal.
But, it depends on the type of woodworking you do. If you do hobby sort of work and you can use a variety of woods, then grab it. For someone that makes smaller boxes, does some turning, laminates different woods and just needs to have a supply of different woods, this would be great.
I tend to do slightly larger things so I like to buy my wood at one time and mill it together, but I have the machines to do so. So, I'd pass.
Its a good deal though, and a very fair price. Also, it looks to be locally sourced hardwood, no exotics (other then the piece of mahogany) which I think is important.