When I was there a year ago, half was protected, but the other entrance you could enter the beach and there were still a few penguins swimming around.
see pictures at:
http://jibbering.com/piccies/2003/04/24/ and
http://jibbering.com/piccies/2003/SLR/Low/04-1/
The cafe next to the beach was also a very nice place for breakfast, and pretty cheap considering the tourist location. There was a hotel there too you can stay in, but we stayed at the backpackers in simonstown.
Cheers,