I finally got around to using this service recently, and had the points not too long after.
I regularly visit Jamie's Italian Perth and find it very useful when booking, and the free 500 points for doing something online that I'd normally do are a bonus as well.
There are many other restaurants available, but most are the higher priced end.
All you need to do is ensure you put your flybuys number in when making the booking - the points will appear in your account after your visit.
I did this over six months ago with Jamie's Italian Perth and did not get the points. Keep your emails.