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from the article: "NASA predicts that 100 million worlds in our own Milky Way galaxy may host alien life."

Sherman Logan: "Classic example of a "scientific wild ass guess" made without any supporting data at all."

It's worse than that -- it contradicts it's own numbers.
Consider, the Milky Way galaxy is said to have from 100 to 400 billion (with a "b") stars, of which supposedly NASA says:

"...perhaps 10 to 20 per cent of stars around us have Earth-size planets in the habitable zone"

Well, 10% of 100 billion is 10 billion, not 100 million, and 20% of 400 billion is 80 billion potential earth-like planets in the Milky Way galaxy alone.
Multiply times maybe 100 billion galaxies in the "known universe", and the number of possible Earth-like planets grows beyond comprehension.

Of course, "Earth-like" does not mean any of them have some kind of life, much less "intelligent life".
That's the big unknown.
Until some evidence is found of any life on any other planet, there's no possible way to guess if we are all alone, or just one of millions/billions of others.

So far the "odds" suggest billions of other, but the facts still say we're alone.

The point of my first post was that we run all of these numbers, and conclude that there are probably X number of planets that have intelligent civilizations (using whatever BS methodology we choose), without accounting for the fact that the duration of an intelligent civilization from founding to self-imollated cinder is but an eyeblink when measured against the ages of the planets. The question of how many planets may have had an intelligent civilization as compared to how many planets have an intelligent civilization at any particular point in time are two very different calculations.

I would say the fats at this point are that we have no data.

Their assumption seems to be that 10% of stars have planets in the habitable zone and 1% of those planets support life.

The problem is that there is no reason to plump for 1%, as opposed to 10%, .000001% or zero. None at all. Percentage just picked out of the air.

Of course, "Earth-like" does not mean any of them have some kind of life, much less "intelligent life".

The most "Earth-like" planet ever discovered is the planet Venus. It is almost exactly the same size as Earth and close to the same orbit. If you were looking at it from several light years away it would be virtually indistinguishable from Earth.