What an amazing spider! I suggest you use that image on google image search (click on the camera when you are on google images) and then it will tell you what it is. I've used it and it works so don't blame me if it doesn't work.
The detail is a bit blurred in the picture, but from what I can make out of the markings I'd say it's a False Widow Steatoda nobilis. You might be able to confirm this one way or the other by comparing it with the pictures here: