I always make sure to include very clear language as to why I am making the connection of the two individuals.  Some personal information does help to create a baseline foundation of trust, but it means more to articulate to both parties how they can help each other.  This helps to drive their conversation and presents a real business opportunity to stand out among the noise of their inbox.  I set reminders on the email in case I am not always copied on the subsequent replies to follow up with the person I am referring to.