While this doesn't mean a top kill can't work, necessarily, it does cut the odds down, depending on where the leak is.
If that is enough to stop the top kill, there remains the relief well option, to get down to the producing formation, fill the existing wellbore with heavy drilling fluid from the bottom, and cement off the wellbore and the producing formation, stopping the oil at its source.
http://tinyurl.com/36rzdy4
A commenter there has this to say about the spot with the 4 plumes.(I have no way to know if it is correct or not but I think it is - just based on observations and other FReepers comments on other threads.)
"There is a choke in the riser - the kink - and also the length itself. There may be some other restrictions as it is 'V' shaped now - kink, down to the mud, up a 1,000' and back down to the mud and along to the exit where the RIT was installed. It also contains the drill string. The kink is the most pronounced restriction and there is enough pressure there for the oil and gas to have eroded the four holes we see in the video now spouting mud."
Would love to hear your views...