synchronicity & confirmation bias
[comment I made in Lethal OD's facebook 09/08/2010:]
Part of Jung's realization about synchronicity is that (regardless of confirmation bias) the fact that your brain and subconscious have noticed a pattern and it has drifted up to conscious realization is the significant part. In other words, it is an internal, not an external phenomenon. The significance may all lie within the subject's interpretation of the pattern he/she is noticing, and not the coincidence itself -- however unnerving. (Just like the famous example of the scarab beetle.)
Of course, all that being said, I think that there is a blurred line between quantum mechanics and solipsism -- perhaps more so than most would like to admit. The unnerving part, not being the solipsism, but the quantum mechanics, which describes our universe in terms that humans can only begin to partially grasp and describe mathematically.