Here is update.. IMHO - This is a done deal..once the sealant is effective, you will have oil & gas siphoned on the tanker.
Right now they are releasing the pressure of oil and gas from billow up.
Earlier, a live video feed of the blowout site, located on the ocean floor about a mile (1.6 km) down, showed the device being placed as oil and gas continued to billow up.
The U.S. Coast Guard in a statement confirmed that British-based BP had successfully attached the cylindrical well cap onto the jagged top of the crippled wellhead assembly using underwater robots, CNN reported.
"The placement of the containment cap is another positive development in BP's most recent attempt to contain the leak," Coast Guard Admiral Thad Allen said in the statement while adding that it would take "some time" to gauge the cap's ability to stem the oil, CNN said.