It's still not a real 18+ rating, it'll just be similar to the current 15+ rating, maybe very slightly more permissive, and most of the current 15+ games will just be rebadged and stuck in the 18+ category. In this country the public has always had to fight long and hard against socially conservative governments to get tiny little increases in what we plebs are "allowed" to view.
It's not going to change my buying habits, I will still get my games from elsewhere, where I can be sure they haven't been modified to fit our ratings board's idea of what games should contain. Screw merely buggering about with R ratings, it's long past time we abolished RC entirely.