Superpings allow moderators to ping any user on the site from the chatroom, even if they haven't been in the chat in the recent past. If the superpinged user doesn't have a chat account because he lacks the required 20 reputation it will be created. This allows moderators to invite new user to the chatroom, typically to discuss their question when doing so in the comments would be unfeasible.
My suggestion is that the "invite to chat" part of this ability could also be added as a new privilege level with the restriction that only "new users" can be pinged this way. The rep required for the privilege and the limit for when superpings stop should be clarified if the basic idea of this suggestion has merit.
Arguments for:
- helps people find their way to chat when they otherwise might not
- chat allows a more nuanced and friendlier interaction with new users
- real-time conversation is more appriopriate to identify and improve a new user's question
- promotes working with new users when their post has problems but has a valuable core question hidden within
- works particularly well for site's where questions are non-technical and can have a high personal impact (Workplace, Parenting, religious sites, ...)
Arguments against:
- may see very little use
- moderators can be pinged from chat to superping a new user (but they aren't always around)
- possibility for abuse? (mitigated by a high reputation requirement?)
- promotes chat at the cost of taking the focus off Q&A ("Participation in SO really revolves around questions, not chat")
- may lead to off-topic or bad questions being answered in chat, bypassing the Q&A framework and site guidelines
I believe the potential benefits to a site's community outweigh the cons I've identified, but I may be missing something. The biggest question is probably if the use and promotion of chat goes against SE's goals or not. I'm of the opinion that chat can be a valuable addition and this would allow for a softer welcome to users that might otherwise be scared away by the abrupt nature of comments and close votes.
Edit: This question originally suggested the full superping ability be unlocked as a privilege. As pointed out by Monica, the intended goal can be accomplished without the actual "ping" by instead giving users access (if they don't already) and simply linking to chat. This has the added benefit of not forcing users into the chatroom if they don't want to (clicking the superping notification will open chat).