Great thread and should provoke some interesting debate.
I remember reading somewhere (not researched by me, so feel free to correct my number if you do know with absolute certainty) that there are over a million Minkie whales estimated to be swimming in the ocean and their population net increases by 5% each year, so that should mean an extra 50,000 Minkies. The current world harvest (for scientific reasons -yeah right!) is around 1000 so 2% of the natural increase or 0.1% of the total population, which should indicate that there is room to harvest more under a controlled quota system to provide a food source to those that want it and yet still allow strong population growth to occur. Obviously this doesn't apply to all species of whales, but certainly minkes and pilot whales are in these sort of numbers.
Still not sure how I feel about whaling in the future or not, but on figures alone, it should be sustainable if managed correctly. I am pretty sure, I won't be lining up for a McMoby