The USCG started enforcing this in the NW about two years ago, it looks like it is being enforced locally now. I got my wife one of these to wear. It stays out of the way. I see others securing normal Type I PFDs to the back of their boards when they paddle.
http://www.westmarine.com/webapp/wcs...10001_99591_-1
If you are surfing close to shore, I understand there is an exemption.