More US-based online retailers—including Dish Network, Expedia, and Overstock.com—are allowing payments via bitcoin. Market analysts say the virtual currency is moving toward mainstream acceptance for online purchases, with full adoption occurring in about five years. Currently, market analysts note, consumers still prefer to use credit cards. Continuing volatility in the bitcoin exchange rate, which is unregulated, is also deterring consumer acceptance. However, merchants like using bitcoin to avoid credit-card fraud and transaction fees paid to credit-card companies. (Reuters)(Mashable)