Not surprised at all. One could argue it was the API that attracted so many people to Twitter in the first place. It seemed really smart to me at first to create such a great ecosystem, but maybe there's more behind that scenes that I don't know about?

Either way it's sad to see this service go. The guy seems nice and provided a good service, but clearly he's not going to spend a bunch of his own time and money if it's not rewarding anymore.