Success in a test tube and/or monkeys doesn't mean much as far as hope for a drug viable for humans. After all, the trials for Tekmira's drug are on hold by the FDA due to safety concerns ( http://www.cbsnews.com/news/ho... ).
I don't know how to ethically do human trials for this. With monkeys, they infect them with the virus, then give the vaccine and see if the animal develops symptoms. Would we knowingly and purposefully infect humans with Ebola? Or are there enough people out there who have been exposed within three days and are as of yet symptom free? The particular strain of Ebola they tested with has a mortality rate of 90% - too high to responsibly give someone.