As with knowledge capture, so must any successful organization pursue training.
Training need not be formal. It can be self-paced, on-the-job, as-you-go, or formal. I know that I have learned the most about the product I support not from formal training, but from actually supporting it.
Part of that is because we have had a tribal knowledge base, that needs to be captured. But part of it is because what we do varies from customer to customer, based on their environment.
Training must also be focused to the folks who will be undergoing it. Some people learn by doing, others by reading, others by hearing. An effective training program in bringing new people up to speed must, then, combine all of those methods. But training cannot last too long as individual sessions. It would be better to have 1-2 hours of training per day, a couple days a week for 3 months than to have it all in one week, 8 hours a day.