The banking system is no stranger to technological advances, whether it is the introduction of data processing and ATMs long ago or, more recently, the creation of online banking. What’s different about the financial technology (fintech) innovations of today is the “exponential” disruption it has made in the marketplace, said  Keith Noreika, acting comptroller of the currency, in this conversation with Wharton finance professor Richard Herring. “There are new ways of doing that very old business of taking deposits, making loans and paying checks,” he said at the recent “ Fintech: The Impact on Consumers, Banking, and Regulatory Policy ” conference at the Federal Reserve Bank of Philadelphia. But a sticking point remains: How does one categorize a fintech company? Should it become a nationally chartered bank? A thrift? A tech company that takes deposits? Depending on which bucket a fintech firm falls into, it would be subject to different regulators and rules.…