best part about d3 right now is the leveling system while everything is being updated. Although Blizzard seems to be quite slow at updating Diablo these days... Runescape updates their stuff almost everyday whereas Diablo players are waiting every minute until the update launches. In actuality I don't allow myself to expect D3 updates.
the auction house is cool if you can really focus enough to understand the small amount you can make to merchant items
i do feel disappointed with the PVP entirely because it's just lame as most of you know D2 pvp was amazing. I also feel disappointed with the RMAH while it was out because of the payment methods but oh well it sucks that i did not have the opportunity to enjoy all of its features. I did try selling items on RMAH but failed and did not have enough time for it anyways.