http://blogs.wsj.com/moneybeat/2014/12/29/bitbeat-bitcoin-bowl-builds-it-but-will-they-come/Bitcoin still remains a small part of the overall payments pie, and determining its exact size is difficult. There is no reliable measure of how many bitcoin transactions are going toward payments. The number of overall bitcoin transaction has steadily been rising, currently in a range roughly between 80,000-100,000 per day. However, given the encrypted nature of bitcoin transactions, it is impossible to tell what the transactions are covering. Trading, legal ecommerce and dark-web/black market sales are probably the three big categories, but we don’t know the percentages.
What we do know is that about 76,000 merchants as of September accepted bitcoin for payments, according to CoinDesk, a number that will surely rise at year’s end. In the past year, a number of increasingly larger companies have tipped a toe in the water, from Overtstock.com Inc. in January to Microsoft Corp. this month, with Expedia Inc., Dell Inc., CheapAir.com and Dish Network Corp. in between. Most merchants, and the major bitcoin-services firms like BitPay, have declined to release concrete sales data.
