It may be no comfort to you that this also happens with my D700, and I think Roger's (NOMAD2's) estimate is about spot on for the frequency at which it occurs with me too.

My old "electronics" instincts hint at classic shutter-switch-bounce, but nowadays it is (I reckon) just as likely to be due to a less-than-perfectly tuned response by the camera's software to my finger's good contact-closure.

Given the relative 'maturity' of (a) tried & tested, gold-surface-to-gold-surface shutter-switch technology versus (b) the D700's complex and specifically-designed in-camera software, I'm voting for a software glitch ... and hoping that Nikon will fix it someday with a firmware update.

(For clarity - "in-camera software" here is synonymous with "firmware".)

Colin P.

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