Hi, just upgraded to 1.0.6.
I noticed that after formatting a Lexar 32 GB the number of shots (R+jpgL10)is now 665, and it used to be around 800 shots for that card.
I loaded an empty "old" card which gave me a free shot count of 807. I took one shot and the free count went down to 664
Did anybody notice same?
I noticed the back focus problem before, but I tought it was my own stupidity. I will try later this week
RAW files are losslessly compressed (that's why each RAW file has a slightly different file size). Generally speaking, higher ISO shots and those from lenses with noticeable distortion (fisheye lenses) compress less, and have larger file sizes. The larger the file size, the less you can fit on a card.

Try this: put your lens cap on, and dial in an exposure of ISO 100, 1/400th second shutter speed, any aperture. Fire off a burst like that and see what the camera reports back as the number of shots the card can hold. I bet the number will be bigger.