Manly fans won't even go over the harbour for games. I doubt they'll take much interest in an Adelaide side.
Sharks have a great nursery but they have failed to expand their brand appeal across Sydney and NSW. Compare them to a side like Souths who have fans all over the place and have essentially moved beyond their simple geographic marker. This is what all Sydney clubs need to achieve to thrive this century. The Sharks are still a 'Sutherland' side but if they remain only a Sutherland side they will fall by the wayside.
As for Panthers versus Sharks there's one key difference - Cronulla won't get a million new people living near it any time soon. The Panthers will. I suspect once the population starts to fill in around the new airport Panthers will in the top 3 of most support Sydney clubs, maybe even number 1. Sharks can't do that.
Mate winning helps... sharks weren't too far off it this finals, they keep it up maybe they do...
As far as appeal, they have roosters and souths to deal with, plus dragons south of them, its a tug of war for all aspects, but they are doing ok, considering the have the bulk of juniors compared to those lot.. my issue isnt manly or sharks, its always been roosters, thet offer nothing to either junior landscape or sydney wide appeal, with no norths, they sjpuld have been one of the most supported clubs im sydney.. but coz they are rich and affluent and well managed, people gloss over them..
They occupy all of 4 suburbs... FMD, no juniors, and coherse the best players from each club, they offer nothing to the league as a whole, but their own existence, and self centred needs.
....But yeah sharks are the issue