Re: Not useful
"We have only a sample of one (here) which is statistically meaningless."
Not really. We know roughly when proto-life emerged from spiral molecules, and for roughly how long the conditions conducive to forming those (or similar) molecular spirals were in existence prior to that. We know roughly the astronomical conditions necessary to producing the planetary surface conditions. From there we can deduce some very broad probabilities.
Thing about broad probabilities is when you combine them, they either splounce out to infinities, or they limit themselves. It happens that these are the sort that self-limit.
I mean, it's not like we have anything close to useful that could guide us where to look. Pretty much the best we've got is "I hope that star isn't exploding or collapsing", (but even that makes an unreasonably big assumption that stellar stability is key to life). We don't really know how old their planets are ... yet. We don't know anything at all about their surface conditions. But that's just the probability for evolving life. Life, it can be concluded, given certain pretty common conditions, is pretty much inevitable.
When you start talking about intelligent life though , the probabilities start to diverge again. Add in technological intelligent life, and the divergence increases. Add in communicative technological intelligent life, and it's almost as useless trying to make predictions about that as it is to prove the existence of a soul .
So it's quite possible that we could eventually make great predictions about where to look for signs of intelligent life  but technological and communicative? You're just going to have to keep that screensaver running and brute-force it.
1. Yes I know, not the Whitehouse. Ell Oh Ell.
2. Pronounced "arsehole", natch.