Northern Sydney Freight Line is a $1 billion project aimed to separating freight trains from suburban trains by building a new track dedicated to freight trains. This will remove what is currently the biggest bottleneck to freight travelling between Melbourne and Brisbane - Sydney. Can't find any images because freight trains don't appeal to the public.
The North West Rail Link is a $8 billion project that runs from existing Epping to Rouse Hill, a 23 km line with a 14 km long tunnel and 4 km elevated viaduct known as the futuristic Skytrain (this name is a bit of a joke). The line will have 8 stations, and there is no indication yet as to how it will be funded or where the trains will run once they reach Epping and Chatswood (the existing lines are already near or at capacity).
The issues that have lead to these two projects is an interesting one, and something that Adelaide certainly can take lessons from. Unlike Adelaide, where rail is being invested in to increase its use, the aim in Sydney has been to ease congestion on existing lines and untangling what is otherwise a very screwed up network. That means getting rid of at grade junctions between lines (like those at Goodwood and the northern Parklands), creating turnbacks and duplicating tracks.