Methinks we're all getting carried away again ... generally in normal conditions 1.3X indicated stall speed will suffice. However:-
Again, I agree with what WCollins says .... what he is saying is that AoA is the all important figure.
Airspeed (esp IAS) just gives an indication and should only be used as a guide. An aircraft will always stall at the same AoA despite airspeed. IAS is a rough way of measuring your AoA under normal flying conditions but that is all! Weight, g, thermal activity, gusts, ect ect will all effect the speed at which you stall ... but not the AoA.
Glider pilots learn to fly by attitude with the ASI blanked off ... still not infallable, but a darn sight better than just learning speeds!
IM