Blockchain.info switched their API away from Mt.Gox, apparently without issuing any kind of notice. You can check the ticker here.
This means that Bitcoin’s price in US dollars is no longer determined by the Japan-based exchange. However, blockchain.info wasn’t the only one to operate this change: Coinbase, Bips and Bitpay also did it, according to Zeroblock’s post on Reddit.
As stated around the web, Bitcoin users are applauding the decision, hoping this change can turn the information about the cryptocurrency prices more accurate in these cases.