I actually want Pakistan to win all their remaining games. Must not worry about whether we play SF at Centurion or Johannesburg. Beating Australia w'd certainly lift the morale and confidence of the team going into the SF
GA, we really shouldn't care about the opponents in the semi final. It should be our job to beat any side at this level. However we should care about the venue since many things can happen on a tricky pitch which could be beyond control. Not matter how much momentum you have and how well you are playing, overcast condition and losing a toss on a tricky Jo'Burg pitch can shatter your dreams in 10-15 overs which I don't think is fair.
ICC and Cricket South Africa did a really crappy job when it comes to maintaining consistency between the two venues in terms of playing conditions.