It becomes increasingly tedious that this question invariably elevates pure speculation to the verge of almost claiming actual science, simply because we can't imagine it otherwise.  Arguments are advanced about large numbers, large numbers of stars, large numbers of galaxies, etc. etc. ad nauseum.

None of that matters.  

The most important question is first; is life easy or hard?

Without an answer to that question, the rest is schoolyard nonsense.

I'm equally disturbed at how blithely we regard our own dominance.  It's as if there is no question that the universe was created for humans to use and abuse. 
On the other hand, we would know that we were not necessarily the pinnacle of creation, that we had kinship among the stars, and that we were not truly alone.
What kind of a question is that?  "Pinnacle"?  This simply displays an ignorance of biology and evolution that is further exacerbated by simplistic declarations suggesting that life must be nearly everywhere.

I am not opposed to individuals speculating about possibilities.  However, let's clearly recognize that it is speculation.  Let's not elevate our ignorance under some hand-waving mathematical probability arguments and pretend that our ignorance is anything except absolute.

Even the questions about finding intelligent life completely fail to acknowledge that we don't even know what such a question means.  As for advanced civilizations?  I have yet to see a discussion that doesn't presume them to be humanity's saviors (1).  
Humans are still primitive, huddling as we do on the knife edge between the heat of our star and the absolute cold of deep space. We’ve barely ventured beyond our planet. Aliens might be to us as we are to bacteria.
This kind of self-effacing nonsense does nothing to advance the discussion.  Humans are not primitive.  Humans are what they are.  Value judgements aren't useful here.  After all, if we consider ourselves to be primitive, what would that mean if we did discover an alien species, that might be further behind us technologically?  Does that suddenly make them "dumb animals" that we can exploit the hell out of?  What would it mean if we discovered alien life and we were the "advanced civilization"?

As to the comparison to bacteria ... really?  I don't think biological ignorance can get more profound.

In short, let's stop the rhetorical nonsense.  Talk after talk.  Speculative argument after speculative argument does NOT create information, nor does it morph into factual data.

Unless and until we can answer basic questions and explore these worlds, then let's recognize when we are indulging ourselves in idle speculation versus "doing science" (2).  

At the end of the article there are some discussion questions to which I have added my own answers.
If it turns out that life elsewhere is extremely rare, what would that imply about the history of the Earth and our place in the universe?
Would the discovery of microbial life be less meaningful or profound than the discovery of intelligent life, and if so, why?
No, and it represents the most likely manifestation of life.
Is it possible for us to talk about the nature of advanced forms of life beyond Earth without  falling prey to anthropocentric thinking?
It's possible, but not likely.  Most such discussions are almost exclusively anthropocentric.
Is the "great silence" meaningful? How many reasons could there be for us not to have any evidence of intelligent civilizations even if they actually exist?
As many reasons as there are stars.  Does anyone truly expect to have cosmic pen pals?
How strange could biology elsewhere be, and might it be unrecognizable? Related to that, how likely is post-biological evolution, where life takes mechanical or computational forms?
This is one of the sillier comments, because (1) it presupposes that alien life is our "toy" to play with and (2) that it would blithely abide our interference.  Instead of recognizing the profound issues that interaction and risk would bring, we get all giddy.  Also, seeing "post-biological evolution" simply reeks of more ignorance and a discussion better suited to Hollywood science fiction than to a serious scientific consideration.
If advanced forms of intelligence and civilization exist elsewhere, are we prepared for that information and how would it affect human culture?
It would have little effect, unless contact occurred.  If there were a more advanced life form in the universe that chose to contact/respond to us, then that would likely signal our destruction/extinction.  [BTW, note the anthropocentricism in case anyone doubted it from the previous question].
(1)  Occasionally one will see a view suggesting that such aliens might be conquerors.  In such circumstances that makes humans about the biggest idiots in that universe.

Frank Drake, eponymous creator of the equation that estimates the number of cosmic pen pals, modestly described it as a container for ignorance.
No, he was describing how his "equation" was a indicator of the types of answers that would be needed.  Not that it be hijacked and used for every bit of speculative nonsense to lend it credibility.  An equation without quantifiable values for its variables [or even what they mean] is not an equation, it is simply a proposed relationship.  It could just as readily be completely meaningless if the wrong questions are being asked.