It would be really nice if the notification told you what part of the comment was considered spam, cause having to go through a long comment to find the exact part the filter doesn't like can be a real pain in the ass.
Not once have I had it look like a URL. It's always been a single word like fun. Seriously, try putting fun in a sentence by itself. You can't, the system thinks that's spam for some reason. And it's not the only one.
Another long comment ruined because somewhere in there somehow it had spam. Nothing that looked like a URL, just normal words and no bloody notification on which part of a whole damn paragraph was the problem. Just spam. Not at all helpful!