CooksSpeculation: If Blizzard follows the same trends as for Cataclysm; you will be able to start doing cooking dailies during the pre MOP launch. There may also be parcels of food available via daily tokens. If you are going for cooking realm first you will want not only the cooking tokens but also the food. For Cataclysm this food is trad-able so presents opportunies to both buyers and sellers.
Even if you are not going for realm first, the raiders that I talked about earlier will want your buff food. I assume that +max feasts will not be available in the early weeks. Do your dailies as soon as they come out. Consider doing them on all your max cooking toons to maximize your tokens and food.
Raiders and even dungeoneers will want food buffs to start dungeons.
Cooking will not be a huge earner (there are few restrictions on the amount of competition out there), but should be good for a few gold.
On that note: Sell your meat. As with all gathering; have a bank alt sitting next to an auction house. Every time you come across a mailbox; send your crap to the bank alt and post it before logging off for the day.
FishingSpeculation: and probably fixed. During the lead up to Cataclysm, enterprising fishermen stood on the boundary of new cataclysm zones and fished away. This was considered 'enterprising' but undesirable by Blizzard; who then turned off the fish catching until Cataclysm was attached to accounts.
Water walking elixirs can help fishermen with reaching hard to get spots.
Fish for feasts are still very much in demand today. I think that there will be some gating on fish feasts limiting this. but I fully expect that for certain fish demand will exceed supply. Look at cooking training choke points and best buff foods, and when feasts are available - what is needed for them.
Anglers; keep an eye out for your new pets; there are lots to be fished up.