It is the later that are more interesting. The discovery of possible Earth like planets seems routine and is, truthfully, expected. It is the more tantalizing prospect of discovering an intelligently produced signal or other measurable indicator intentionally transmitted that fires the imagination. Although this story still hasn't topped the normal media channels, the account of SETI's investigation into a signal coming from HD 164595 has as much, if not more, steam behind it than any other similar story.
Centauri Dreams provides a more detailed presentation of what we know so far:
The signal was received on May 15, 2015, 18:01:15.65 (sidereal time), at a wavelength of 2.7 cm. The estimated amplitude of the signal is 750 mJy.
No one is claiming that this is the work of an extraterrestrial civilization, but it is certainly worth further study. Working out the strength of the signal, the researchers say that if it came from an isotropic beacon, it would be of a power possible only for a Kardashev Type II civilization. If it were a narrow beam signal focused on our Solar System, it would be of a power available to a Kardashev Type I civilization. The possibility of noise of one form or another cannot be ruled out, and researchers in Paris led by Jean Schneider are considering the possible microlensing of a background source by HD164595. But the signal is provocative enough that the RATAN-600 researchers are calling for permanent monitoring of this target.
The significance here is two fold: 1) thus far, it is measurable/detectable and 2) there is at least one legitimate research telescope station advocating for further study of the target. Yes, it could be other things, but SETI is notoriously conservative about raising any possibility of a given signal warranting attention. Add that this data has apparently been studied for just about a year and half before the story broke, and one suspects that the signal detected is outside of the ordinary and otherwise expected.
Of course, measurable signal or no, the daunting mathematics behind several possibilities aligning at once is nearly indomitable. The universe is a vast place and for this to be the "real thing" one has to have several variables line up: 1) there is other life in the universe; 2) there is other intelligent life in the universe; 3) there is another civilization in the universe that has mastered at least our level of technology and is transmitting signals into space; 4) the signals of the advanced civilization were directed to our corner of the universe; 5) all other possible sources of the signal have been investigated and cannot be a reasonable source.
But what if everything aligns? What if this is it?
To be clear, I believe that given the enormity of the universe and the mechanics of creation, it is more than probable that other intelligent life exists in the universe and, like us, has at least a passive interest in searching out other civilizations in the hope of proving it is not alone.
Furthermore, I believe it is inevitable that we will at some point confirm the existence, at one time or another, of said civilization.
It remains to be seen if this signal if the harbinger of what one can only suspect would be paradigm shifting moment. It is not the prospect of discovering intelligent life itself that takes us to precipice of a new epoch. Rather, it is the prospect of coming face to face with life that is equal to or greater than our own which provides for both anticipation and anxiety.
Invariably, I would ask the question, if we can demonstrate a high civilization exists, what is the probability that at some point in humanity's distant past we had some form of interaction with a civilization more advanced than our own? What does such a civilization mean for our philosophies and religions?
I suspect our conception of God would go through some form of re-emphasis. In the Judeo-Christian tradition, we could anticipate a pivot to the Wisdom literature and perhaps later Apocalyptic texts, filled as they are with abundant symbolism and cosmic imagery.
The more immediate question is clear: is this really it? I suspect, when all is said and done, the odds favor this being another "big wow" moment, a one of anomaly that is never repeated, but otherwise suggests an artificially occurring signal. And that is most disappointing. Where post-modern humanity (in the West) has determined that there is no reference point or subject of reality other than itself, perhaps the indication of the existence of an intelligence greater than our own is capable of realigning the collective philosophical view.