[codeshaman]

I would venture to say that most educated people allow for a pretty high probability that life exists on other planets in the Universe, given the sheer scale of the place.

In fact, a much harder task would be to prove that life absolutely doesn't exist anywhere else in the Universe.

So we instinctively believe, but we still want proof. So would the SETI thing provide that definite proof ?

In many ways this is similar to 'does life exist after death'. Either way you stand, it's impossible to absolutely prove it, but some day everyone will definetely find out ;).