Our API directory now includes 56 billing APIs. The newest is the Merchee API. The most popular, in terms of mashups, is the Stripe API. We list 5 Stripe mashups. Below you'll find some more stats from the directory, including the entire list of billing APIs.
Singapore's OCBC continued growing its banking API portfolio with the the GIRO API and sandbox versions for four transactional APIs (Account Balance, Account Transaction, Merchant Card Payments, and Pay Anyone). The bank has partnered with the Singapore government for its first implementation.