If you're helping somebody solving an interesting issue, summarize your experiences with something or write anything that might be cool to be around in a couple of years as well, you do provide potential high-value content. The message in this talk to all those authors is: don't use web-based forums.
Unfortunately, all content of closed, centralized services will be lost in the long run. This talk will give examples from the past where human kind lost many important contributions.
Therefore, it is necessary to choose the platform you contribute to wisely now instead of learning through more large data loss events later-on. The talk summarizes the dangers and provides positive examples how loss of knowledge can be minimized in future.