nah Mace Windu survived the dismemberment, the lightning, the fall, the landing, the Sarlaac pit, and the carbonite freezing process... in that order...
he fled to Alderaan, to rally the Rebel Resistance with Bail Organa.
This is why we don't see Mace (or Bail Organa) in Ep 4, because he/they were on Alderaan when the Death Star floated up and blasted the planet.
Mace Windu and Bail Organa's were but a few of the thousands of voices Obi Wan Force-felt/heard crying out in terror, before being suddenly silenced...
so, there you have it; Mace survived Ep 3, but died off-screen in Ep 4!
Happy now???
He died! ok listen even in the slight chance he lives, lets say the fall don't kill him.. well they would show him so that idea sucks but in the slight chance, he would have been killed very quickly, all the jedi were killed during order 66. anakin probably would have hunted his ass down anyway. but that is a long way away from the truth. face it Mace Windu got his hand cut off by Anakin, and then got zapped by Sidious and fell out a window.
That is like the coolest picture I have ever seen, PVS.
http://www.starwars.com/databank/character/macewindu/index.html
Read the last paragraph.