I have also had the same issue, I will explain my experience below:
I link Google contacts (primary), Facebook, and linked in. One day I noticed a contact I have in facebook was linked to a google contact. The facebook contact had email and the google contact had email, address, phone, etc.
I received a text from my google contact, and it appeared as it was from the facebook contact (picture and all). I then deleted(unlinked) my facebook account on my pre. This solved the issue, but is not acceptable.
Like an above poster said, when you search synergy, the name will appear as the primary name in the system - kinda a pain when you are trying to find one name, but another appears.
Later, I re-added my facebook account. Everything appeared normal and then a few days later I noticed the same contact had been linked together. But this time it appears as the Google contact (the first time it appeared as the facebook contact), BUT the picture (profile pic) is still originating from the facebook account.
Anyone have any updates to this problem with this bug? Palm? HP?