Even among SETI professionals, there are many who dispute my SETI strategies, but I still think radio telescopes are the best way, with our present technology, to search. Even if most other technical species in the Galaxy have access to some communications technique we haven't discovered yet, there are still very good reasons for people to broadcast and receive in the radio spectrum.

For starters, the universe is extremely quiet in some areas of the microwave spectrum, and very transparent. Of all forms of electomagnetic radiation, the signal/noise ratio is best there. Second, there will be a strong incentive for species with interest in astronomy to develop microwave technology because so many natural emitters representing important physical processes are located in that band. ET may use tachyon beams to talk, but they'll still be monitoring pulsars and the 21cm and 3degK hum. And they know we'll be listening there too.

Granted, if ETI's tech is not physics-oriented, there's no way we can get in touch. But there's not much we can do about that, is there? Sometimes we have no choice but to look for our car keys around the lamppost.