Exactly. I think I asked this earlier in this mess. The Obama admin near an election likes to NOT fess up to ANY folks that are ON THE RUN, ya know.
I don't think it's that parochial. Malaysia could have asked Boeing for the data as well, even though Boeing says that Malaysia Airlines didn't sign up to receive the data itself (apparently Boeing always gets the data even if the airline involved doesn't want it). I suspect that the US gov't, various European gov'ts, and possibly the Malaysian gov't, knew about the data and knew where it had gone, but didn't reveal that knowledge because they didn't want to tip their hand to the hijackers that they had a pretty good idea which direction the plane had gone. That would have made it much easier to catch the hijackers if/when they revealed themselves by, for example, making a threat or a demand for ransom.
If that were the case, they would still need the search and rescue effort to take place - and they would need it to take place at the last known good location - or else the hijackers would suspect something was up. My guess is that the information finally became public yesterday because either (a) the governments involved never received any threats or demands from the hijackers and finally concluded that the plane had most likely gone down - it could be as simple as something like the hijackers assuming the plane had more fuel than it actually had and they just ran out of gas over the ocean before they got to their destination - or (b) it became impossible for them to keep it quiet any longer once some journalist dug down deep enough to find the tidbits about the maintenance data being sent to a satellite uplink - which would explain why the first stories alleged that Rolls Royce had been getting data because the typical descriptions of these systems focus on the maintenance and engine-performance uses of the system.
So, as of yesterday, the jig - whatever it was - was up and now the true likely location of the aircraft has been released to the public because either the secrecy is no longer needed or because it can no longer be plausibly maintained.
I'm going to hazard a guess that the governments involved came to the conclusion on Wednesday that the plane had most likely run out of fuel and crashed into the Indian Ocean, which is why they no longer needed to keep the fact of the data transmissions secret any more.