The Taronga Zoo is a must-do if you're not going to one of the out-of-Sydney wildlife parks (which I actually prefer). However, the Zoo is close in to the downtown area and so if you don't want an all day trip to a wildlife park, it is a great option.
To our surprise, the combo harbor ferry-zoo pass wasn't as cheap as a combo Capt Cook Cruises/zoo pass - we'd have thought the city ferries to be cheaper than the private enterprise cruise line.
The 'cuddle a koala' experience is now 'stand sort of close to a koala' - not quite the same thing at all, but perhaps better than nothing.
The gondola ride was great (and costs no more than walking or taking a bus to the main gate, so very recommended).
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