I think something that may encourage users is if they are greeted with a warm welcome. The only time I really see users being welcomed is with a cookie cutter "Welcome to Skeptics!" and then being asked to provide references.
I've also seen new users ask questions or give answers without any welcome or acknowledgement that they are new, or in some cases having their first questions closed without further discussion.
- Does sharing a shower use less water?
- This answer to a question on car alarms preventing theft
- This answer to a question about refusing US currency
- Is water or tea dangerous for young infants?
From what I have gathered on other SE sites, users with less than 10 rep are pretty much always welcomed with links or invitations to join the chat. I think it would be a good idea to adopt such a policy, esp when we have a higher standard of quality than other sites.
An example might be something like:
Welcome to Skeptics.SE! Feel free to join the chat, look at some of the issues being discussed in our community or participate in the topic of the week program. If you have any questions, check the FAQ or ask in chat where someone will be happy to help.
That's not necessarily a great example but I think it gets the idea across.
I will start to do my part, but I think it would be good as whole if the community could be more welcoming wherever possible.