We have now discovered dozens of stars with planets. We now know they are out there. As our instruments and techniques improve we will find more and more, and some of them will be earth-like and capable of supporting life as we know it. Of course, there may also be life as we don’t know it, too!
Will we wake up one day and find communication from ET calling us? Not likely. Carl Sagan figured it out. The distance of space and the limit to the speed of light (and radio waves) mean that even if we did get a message it would be from so far in the past that those who sent it would certainly be dead and, in all likelihood, the entire civilization that supported them would likely be dust.
But did Carl know about strings?