It's an interesting idea and if the 405 seat boat he is introducing can operate at high speed (over 80 kmh), then it has a chance of success. The direct Portalington service makes sense as the land route to Melbourne is rather circuitous, but it is hampered by a frustratingly low speed limit in the Yarra River as it approaches the city. So he is considering running the Geelong service to Station Pier if the state government fulfils its promise to extend the 109 tram line on to the pier (don't hold your breath, I doubt the government will extend the tram). But a ferry run to Station Pier would require city bound passengers to transfer to a tram, meaning the journey wouldn't be much faster than a speed restricted dawdle up the Yarra like the current Portalington ferry.
So with the handicap of either changing to a tram at Port Melbourne or the ferry having to massively slow down in the lower Yarra, I'd be doubtful if a Geelong fast ferry will ever be introduced, if another outfit was proposing it, BUT Paul Little has strong record of running ferries on Port Phillip, plus there is a media release about the Geelong ferry proposal on the Incat website. Incat has built a lot of ferries that go up to 110 kmh and they are about to finish building Hull 090 for an undisclosed buyer. Hull 090 is only 35 metres long, much smaller than the larger ships Incat often builds, but ideal for a smaller operation on sheltered waters like Port Phillip.
Anyway, do people think a Geelong to Melbourne fast ferry has potential? Would people use it rather than the train?