I've been a professional software developer for about 15 years now, but have only been participating in SETI sporadically for the last couple years. I'm trying to throw a little more CPU power at the project now since the new BOINC clients are so well-done.
If an extra-terrestrial signal is discovered by SETI@Home, I think the unifying power of that discovery will be good for the human race as a whole. We also have to keep in mind that even if the galaxy is teeming with life, the odds of discovering a signal are still pretty low due to many other factors. So don't get discouraged and keep crunching those work units!