It's a net gain for those rescued, a loss of face for the rebels, and, yes, I would agree that the remaining hostages are now more endangered.
The rescue was bloodless which is amazing. My cynical side wonders if someone was bribed as well. I do favor bribery over fire fights and collateral damage.
The fact that Presidential candidate McCain was touring Columbia at the time was probably a coincidence. If he were photographed on the rescue heliocopter my cynical side might just kick in.