I've been to Victoria Falls several times and as beautiful as they are it just isn't worth it anymore. Since the Soccer in2010 the price went up to $30 but hasn't come down. To pay $30 to walk through and get soaked just isn't worth it anymore.
Having just visited - May 2011 - there was plenty of water going over and photo opportunities limited unless you have a water proof camera it seems ludicrous to pay $30 to see what I've seen many times before.
If it is your first trip then you HAVE to do the Falls but for return visitors save your money as you are now paying more for nothing new!