Seth Shostak from SETI published this piece yesterday on the time related difficulties in finding life outside the solar system (and holding a conversation with it). He even through in a nice mention of Long Now:
“There’s a similar argument to be made for communication. We seldom initiate information interchange that takes longer than months (an overseas letter, for instance). More generally, we seldom begin any well-defined project that lasts more than two or three generations. The builders of medieval cathedrals were willing to spend that kind of time to complete their gothic edifices, and those who bury time capsules are occasionally willing to let a hundred years pass before the canisters are dug up. But what about a project that takes several centuries, and possibly millennia? Who’s willing to do that? Only Stewart Brand’s “Long Now Foundation” seems to have the guts for this type of enterprise, proposing to build a clock that will keep time for ten thousand years.”
Jill Tarter from SETI also discussed these issues in her Long Now Seminar back in 02004.