Canon may have problems with the light-leaking issue of the EOS 5D Mark III, but Nikon has also some problems to deal with. Nikon’s new full-frame flagship, the D800, is reported to “explode”. This is the second forum post I found about this issue (another one here). So, if you want a new FF camera you can choose between one that’s leaking light through the top LCD panel, or to get one that will explode in your hands. Hard times for photographers!
UPDATE [thanks to Bobby]: nikon rumors reports that Nikon is recalling batteries that are used on various cams, the D800 included:
Today Nikon recalled some of the EN-EL15 rechargeable Li-ion batteries [...] that are used with the Nikon D7000, D800, D800E and Nikon 1 V1 cameras. The described reason for the recall is overheating. There were no overheating cases reported from users, the problem has been discovered during the manufacturing process.