I'm not able to give you an appraisal as I am not a pro.
However, I also have a couple of bitcoin themed domains, such as freebitcoinonline.com and billionbitcoin.com. Both are on godaddy auctions and have been for a couple of months now. I haven't had a single view or offer. If you have a look there are a ton of bitcoin themed domains listed on go daddy auctions. The bitcoin currency is still in its early stages so it might be a while before we see the value of bitcoin domains go up or possibly down depending on how well bitcoin does.
Something like bitcoinexchange etc. Would probably do very well.