thanks for the url! I guess we now know why sagan things other beings would be able to figure it out, he headed the committee that did it!
seriously, assuming we do want to communicate, I think this is the only way to try it (at least at the time). The odds against it ever being found are astronomical, but it is a potent symbol for us back on earth. Sort of like a funeral really being for the living....
Overall, I think the selections for the record are good. You could always argue about what is there and why, but a selection of natural sounds and human sounds is a good choice.
What about this thought: The craft is found in the future in a similar way that charlton heston found the statue of liberty in the planet of the apes (modified for space flight, of course)?