There are many people who in waiting for a savior or something to believe in to tell them how to act and what to do. This belief is the confirmation of their existence and reason for living.
My uncle, who is in his mid-sixites, first saw this play performed in a catholic boy-scout's hall (a venue of which Beckett would have approved), and said that if one had grown up in post-war Ireland, as both he and Beckett had done then the meaning of the waiting would have been perfectly clear. It was a mind-set prevalent at the time, and one Beckett alternately suffered from and rejoiced in.
It is also worth noting that this play, as with many of his others, such as Play, are situations in suspension. Time is of little relevence. I realised while playing Pozzo that it is irrelevent which act preceeds which, except for the smallest points of continuity. As far as the story is concerned for instance it is of little regard whether Pozzo was blinded in act one or act two.
As such, Beckett is taking a moment of life in isolation and examining the human condition.
However what keeps me returning to the play is the great humour - perhaps the morbid gallows humour we all exhibit in the face of depressing circumstance. The hat exchange in act 2 cracks me up every time.
Nothing to be done.