Engadget - The rumors and leaks go back a bit further, but it was a year ago today that Google officially revealed its Google Wallet mobile payment service -- a platform that the company is still betting big on, even if it may be slightly reconsidering the way it does business. While it might not have taken off quite as quickly as Google would have liked, the past year has still been a fairly eventful one for the service -- albeit occasionally for reasons the company would prefer you forget -- and the next year proves to be even more challenging as the service faces increased competition. Read on for a look back at how we got here, and what lies ahead for both Google Wallet and mobile payments in general. (Google Wallet, Services)