One thing to keep in mind regaring stall is that it's 100% dependent on angle of attack, not speed (something Popular Mechanics gets entirely wrong). What happens basically is that at a high angle of attack the air layer doesn't track the wing surface properly and so you are deprived of standard lift. With certain aircraft designs (SR-71 for example) this is very hard to make happen (but the SR71 can stall it's engines before the wings stall due to AoA).
If you are faced with a stall, I would expect the first thing to do is to pitch down to reduce angle of attack then accellerate and pitch up to get out of it. T-tail designs are generally disfavored because the elevators can get blanked by the wings in a deep stall, but with the A330 this isn't an issue as it doesn't have this tail design.
I find it puzzling that a professional pilot would pitch up in response to a stall warning. Popular Mechanics is right to flag that is as difficult to understand.
In "normal mode" the computer will not let pilots stall the plane, whatever they do; it will accept the commands up to what it considers dangerous. There's an "envelope" of acceptable plane movements; pilots can move inside this envelope but not outside of it.
In "alternate mode", the envelope is much wider and you can actually stall the plane.
If you're in normal mode, it makes sense to pull the stick all the way so that you're at the edge of the envelope: you climb as fast as you possibly can (as fast as the computer will let you).
And you can probably fool yourself when the stall alarm rings: the computer is telling me I'm near stalling -- I'm at the edge of the envelope, THIS IS WHAT I WANT!!
In fact you're not in normal mode anymore, and the computer is telling you that you're way past the envelope. But you can't register that, because for you that is simply impossible.
If that's what happened, the cause of the crash is insufficient training in alternate mode.
But to me the bigger problem seems to be that such an important change in the plane's behaviour could happen without anyone noticing. I'd consider the mode to be something the pilot must be made aware of, not something he has to deduce from the fact that the airspeed isn't available.
Perhaps the mode is shown prominently and the pilots just didn't notice it in their state of panic. Making it more prominent probably leads right into an insane arms race - the stall warning was as prominent as anything can be and still got ignored.
I don't envy the person who has to design a airliner cockpit's user interface and decide which of a hundred potentially vital pieces of information should be displayed how.
In the flight recorder log, at 2h10m05s, there was an audible "cavalry charge" alarm that indicated to everybody in the cockpit that the autopilot was disconnecting (plus message at the same time on the ECAM).
Then, on the ECAM message console 1 second later, the message "F/CTL ALTN LAW (PROT LOST)" was displayed: alternate law, protection lost. At the same time, Bonin said "I have the controls", which to me indicates that he knew that the autopilot was off and that alternate law was engaged.
 Page 45, http://www.bea.aero/docspa/2009/f-cp090601e3.en/pdf/f-cp0906...
 Page 88, Ibid.
If that's not the case, and the stall warning sounds even when there's no real danger of stalling (because the controls are operating in normal law), I feel like that's a terrible user interface.
If the flight computer is having to intervene and change the flight controls, then at the very least there should be a force-feedback mechanism in the stick which tells the pilot he's doing something wrong, and that he really shouldn't be yanking back the stick that hard.
The other bad part of the user interface is that the two sets of flight controls are not linked, like they were in the old days. With side sticks, it is not easy to see what the other pilot is doing. And averaging the control inputs of the two pilots is INSANE, in my opinion. Only one pilot should be flying the plane, and it needs to be quite obvious who that is at all times.
The CRM mechanism to take over flight controls should not be saying the words "I have control", it should be flipping a big switch on the center console that visibly indicates who has control.
However if you add force feedback of the plane computer "correcting you" you'd never know if it's plane or an another guy. Therefore, force feedback from the computer doesn't sound to me as a good idea. Some kind of feedback would be a good thing, but in panic, it wouldn't be noticed. I guess I'd put something like something "protruding up" on the stick when in another mode -- you'd feel and see it.
Finally, switch flipping is unnecessary if you have a force feedback. It think that's really the major feature missing!
Once your instruments start failing left, right, and centre you should go into what I call "advanced free fall" mode, check horizon (true, false or otherwise), check altitude, check parachute, repeat... If you hit gimbal lock (or similar INS failure) in the dark, well just bend over and kiss it goodbye.
One problem was that the stall warning stopped due to high angle of attack even though the plane was stalled, and it started again when the nose was lowered and the AOA was in the "valid" region again. This might have confused the pilots in a situation when they already had inconsistent airspeeds etc. to deal with.
I'm sure that the flight training will also be investigated, there has been concerns that improper stall recovery technique is being taught by some instructors: http://www.caa.co.uk/docs/33/012010.pdf
(And of course, in planes that are not certified for stalls, you can't really practice full stalls and have to train on approach to stalls instead.)
Of course, very little airliner training happens outside a simulator, which can you can stall without damaging anything.
You should get an introductory flight lesson, then you could ask do have a stall demonstrated and see which flight simulator matches best. There are a lot of signs you don't get outside a full motion simulator, such as wing buffeting and "mushy" controls.
It's the stalls caused by uncoordinated flight during a steep bank or snap spins caused by exceeding critical angle of attack, regardless of speed, that will kill you. The first is easy to get into in a trainer like a C172. The second won't happen (safely) unless you're in something with a bit less lift and more power, like a Pitts.
Maybe they should apply mild taser shocks to pilots stalling in the simulator. I'm not being snarky. There should be some kind of physical consequence of making bad mistakes, otherwise it's too disconnected from reality.
A simulator "crash" is not nearly significant enough to their reptilian brain. Their neocortex may register it as a failure, but for the reptilian brain is just a big nothing.
Adding some physical jolt may drive the lesson deeper in their psyche, that a crash really is a bad thing.
Actually, most fatal crashes are "stall-spin accidents", where pilots stall the airplane near the ground without sufficient altitude to recover. But those are not cases where you keep the airplane in a deep stall for 90s. When you stall an airplane in VFR, it's obvious what happens.
No one would persist in keeping the airplane at 20 degrees positive pitch while descending at thousands of feet per minute without realizing the airplane is stalled. But here, without outside references and with obvious confusion about the state of the airplane, it was apparently beyond these guys. (Except the captain, whose comment about "no, don't climb" seems to indicate he was on the right track, but by then it was too late.)
So the air layer on the back "peels off", and you have turbulent flow on the back, instead of laminar, is that right? So the negative pressure is greatly diminished.
While the degree of stall with respect to the wing is independent of airspeed, the effects of stalling on the aircraft are very much dependent on speed. Even with the wing in the process of stalling, it can still generate enough lift to keep flying if you're going fast enough.