It’s been revealed the 9 member girl group will have a sub-unit soon. An official had this to say:

“It is a high possibility that the album may be one showcasing the vocals of the vocally talented members…It is expected that there will be a unit of 3-4 members from Girls’ Generation. There is a possibility that the plan will change.”

SM had this to say:

“Nothing has been confirmed about a Girls’ Generation’s unit.”

If it is a group to display vocal ability, my prediction is: Taeyeon, Jessica, Seo Hyun and/or Tiffany. What do you think?