Come on guys, the mystery isn't, see the section "Manual White Balance" in the following page:
http://www.dpreview.com/reviews/olympuse10/page6.asp
You are right for sure.
Pentax already has used this symbol in Optio menus for manual white balance.
You can see it at http://www.steves- digicams.com/2002_reviews/pentax330gs_pg3.html
(the menu image (third from top) is animated, and when it comes to the "White balance" there at the bottom can be seen this "mysterious" sybol).
Ed
