Not so fast smurfjet, supermunk has it right. IAS (indicated airspeed) will show a similar speed approaching the stall, to that at lower altitudes, simply because the amount of air the wing sees near the stall and the amount the airspeed indicator sees are both similar to lower altitudes. Higher TRUE airspeed takes care of the lower air density...
Lots of books cover this stuff, and go into the real detail of angle of attack, load factor and why planes suddenly start to feel really unsteady towards a stall.
Here's a real good reference:
http://www.monmouth.com/~jsd/how/