Square Enix Trademarks 'Circle of Mana'
Square Enix has filed a number of trademark registrations in Japan, including Circle of Mana, Wizardlings, and Agent 47. As with all trademark filings, this doesn't necessarily mean they'll be turned into actual games. The last Mana game released was Heroes of Mana in 2007 for the Nintendo DS.
Additionally, Siliconera points out in an earlier report Wizardlings may be developed by Square Enix's North American branch.