Interesting... If we are to observe intelligent life in our lifetime it seems as if this route is more likely than direct contact.

That sad truth about the universe is that you can't go faster than the speed of light. So if you assume that intelligent life takes roughly about the same amount of time as our civilization to form and develop space ships it may be impossible to have reach us by now or impractical to. This works the other way around too. If we are looking at a binary star system that might have intelligent life we are really looking X years into the past where X is the number of light years they are away. Adding to the problem that it might take a long time for highly intelligent life to form and reach the kind of state suggested.

It's an interesting question to pose, what telltale clues could you infer from a binary star system that would suggest there is life on it. I suppose when analyzing the metabolism of these binary star systems you would want to look for something that looked more like an engine and less like a firework to truly determine if there is life out there.