I’ve been on the hunt for some good webcams of the surf, aka surfcams, and so far I’ve only managed to find one in Blouburgstrand. It gives you a good idea of what’s going on though.
Thanks to Rob in the comments who let me know about this page that pulls together a bunch of web cams: http://www.xplorer.co.za/local/webcams/
This web cam seems promising, you can check the surf in the foreground: http://www.tablemountainview.com/
As per the comments below, if you have a Blackberry or Android device you can download an app and have the webcams on your phone. Check it out here: http://www.beachwatch.co.za