Cape Town, summer break in winter time

I think it is better to spend one day in Cape Town than one week in Johannesburg, the weather here is much better and there is also a very nice beach life and mountain sightseeing as well, whom looks like a tourists & backpapers gotha. What I think they need to improve is the security for visitors, being alone in the night it is not good for yourself, even here.... I do not know how South Africa is going to handle this kind of stuff for the world cup, but I felt myself totally unsafe in the night both in Joburg and Cape Town during my visit.