Other than the rather obvious fact that the spill's repercussions on gulf fishing will be very, very, very bad in general and worse than that in certain specific areas we don't have a really good understanding of what, exactly, will happen where, and how bad things will be.
No one's ever created fractionating columns which run hundreds and even thousands of feet -- which is pretty much what the plume is -- while the "volcano" itself creates a 5000' column. Exactly where each fraction will concentrate after being carried by currents which go in all sorts of directions depending on depth, microclime, and so on... All I can say is, "oy."
When I was an undergrad, I took all of the pre-med chemistry classes, which doesn't make me anything more than barely literate as to the chemistry. And I'm certainly no oceanologist or biologist either -- again, not beyond bare biological literacy. I'm no math genius either, but that's mostly what I did study and have a math appreciation of the difficulties of coming up with answers to fluid dynamics and "chaos" statistics problems which contain huge numbers of variables and elements. This time, mega-oy.
What I'm getting is that no one really knows how long it's going to take for the fisheries to return once BP or the government or whomever figures out hows to cap the leak; and anyone who says they do is trying to sell you something.
Furthermore, we're just as hazy on the pure cause and effect health effects (eat so much of this and that will happen) and even dimmer when it comes to the more stochastic epedimiology (i.e., that cancer rates will rise by X%, doesn't mean that a specific tumor on a specific person was actually "caused" by a given event). The Gulf wasn't exactly what you'd call pure, anyway.
So... it's all very confusing and frightening. I hope the well gets capped, and I hope the effects are less extreme and don't linger as long as I fear. I also hope that the agencies responsible for disseminating information do that as information becomes available. I'm neither a mushroom nor a child, and don't appreciate being left in the dark.
Bottom Line: For now we know very little other than the short term problems with our seafood supply will be big and expensive, and we can also be assured there will be all sorts unexpected consequences.
BDL