So the direct consequence currently is that millions of barrels are venting directly into the gulf. I'm not too clued up on crude oil, but as far as I'm aware, oil is less dense than water, thus rises. Gulf currents will dissipate this as seen from aerial photos, so without containment, oil will end up in a lot more places than just the gulf.

How is the oil flow being contained, and how effective is this - remembering there may be billions of barrels to be contained...

What percentage of the oil will be sub-surface - a lot harder to contain. And how can this be contained?

What are the flow-on effects of a possible sea-floor collapse and how much of an impact will this have on the structure of the gulf?

And then the overriding question of all - is it worth it?

If there is a relatively easy way to extract crude from the water, it may in fact be more economically feasible to extract the oil by destroying the well than to repair the well itself. Of course, none of this is taking into account the environmental impact...