Current weather is ideal, and 50-60% of the oil that hits the surface is being recovered by skimmers, burning is working well as well and the dispersants are resulting in not much oil reaching the surface. (From the Admirals press briefing)

This is wonderful, but these numbers will decline dramatically if the favourable weather changes. Also, it is really a complete unknown what effect the massive plumes of sub-sea oil caused by the dispersants will have on the ecology. First measurements are very favourable, with dissolved oxygen levels within range. But this could change as new data is collected.