Yes, the Datasocket stuff is free to distribute. It's in a library included in CVI, so it's covered in the CVI license agreement and distribution requirements.
Here's NI's software license agreement. http://www.ni.com/legal/license/
Paragraph 13 covers Application Deployment. Paragraph 13.B. covers fees and states that "Generally, you may distribute, deploy or otherwise make available Authorized Applications without paying additional fees to NI." It then goes on to list the exceptions where you do pay a fee for deployment, but CVI's Datasocket is not included in the list of packages requiring fees.
I also confirmed this with our NI Sales Engineer.
