The beta was alot of fun and also extremely limited, you can only play through the hour worth of content with each class so many times before you burn out. So now all there is left to do is wait, I don't think anyone should be disappointed in the final product.
The amount of items listed on the AH in the beta is very large, almost overwhelming...so I can only imagine how truly overwhelming it will be after release. The AH does have a very powerful search tool which allows you to narrow your results to exactly what you are looking for. I could see sellers 'advertising' their tradelists on the forums to get more exposure though and doing the transactions through the AH.