Given someone playing a game could click a link thinking it's part of a game and end up with all manner of nasties on their pc as a result? This happened to me (not the nasties, at least I hope, but going to an external url when I thought it was an in game link) when I was looking at that dodgy porn game submitted the other week. It's well open to abuse and without any prior warning.

I think you make a good point, but I would guess it would be hard to do.