All good points from TeamSpeed.
When i got mine i went out and shot a load of shots, got back home, and was disappointed with the results.
It was time to step away from the camera, have a look at why things had gone wrong, as it turned out it was my lazy shooting style that caused the problems. I let the camera dictate the settings, all were in poor light with gloomy, dark, overcast conditions and the resulting shots mirrored these conditions.
Once i took control and set the camera to M or TV mode, i upped the shutter speed to twice the focal length, that cured the blurry or as some have said OOF shots by eliminating motion blur. I set the iso to Auto and made adjustments in camera to what i wanted as my maximum, set my F setting to two stops above the lens, ie, f5.6 lens then i set the f setting to f7.1 (these are only a guide as to when "i" started to see improvements)
These settings were the point where i started to see massive improvements in my shots instead of shooting in AV mode for practically everything as i have done in the past, and also using the correct focusing points for what i was shooting at that time.
Good luck with yours, and post some of your shots and findings 