I would have to agree with many who have already replied.
I think that, by the numbers, life is extremely common in the universe.
That doesn't mean intelligent life is common, it just means that life itself is.
There could be life out there that is far stranger than anything we could imagine.
Life in gas giants, life within stars, life native to the vacuum of space, etc etc.
Nobody knows, you cant reply on probability to let you know.
It would be like saying how many times will you get heads if you toss a coin 100 times. The probability is 1 in 2 so you would expect get 50 but you
could get none at all or you could get 100 the 'probability' is the same. Probability has no real effect on the actual result.
So the Drake equation is really a waste of time. You simply have to go out and check to find out.
edit on 28-1-2012 by PhoenixOD because: (no reason given)
I tnink life is a condition you will find common over the universe...all kinds of it...wherever the can be life i guarantee you it will be
there......
from the macro to the microscopic it is endemic.