Yep, it's a 'tell-tale' hole under the engine, the idea is you know the seal has gone before too much water gets past the seal and contaminates the oil damaging the engine. Happened on my second fazer, I spoke to a friend who is a Yamaha tech and he said not to worry about it to much unless the leak is really bad, I ran my bike for nearly two years before I sorted it although my leak was very slight.
The good news is it's not too big a job to sort, remove exhaust, sump, and you can get access.
Jim.