Nikon is recalling a specific series of EN-EL15 batteries due to overheating risk. The EN-EL15 batteries are for the D7000 and D800.
More info on how to check your battery and links to Nikon service pages (US and EU) on nikonrumors:
http://nikonrumors.com/2012/04/24/nikon-en-el15-rechargeable-li-ion-battery-recall.aspx/#more-38792
