Canon has recently released firmware update 1.0.7 for its EOS 5D Mark II DSLR camera. The firmware is intended to improve and mitigate two image quality issues that occur under certain shooting conditions.
One issue is the presence of a "black dot" appearing on the right side of a point light source when shooting night scenes. The other is the appearance of vertical banding noise when shooting in sRAW1 mode.
Canon suggests that, when you update your firmware to version 1.0.7, you also update the Digital Photo Professional and Picture Style Editor software.
Additional information, download links and updating instructions can be found at Canon's Website.