Please stop using "I don't know where the QR will take me" as an excuse. Any decent scanning app shows the QRs content before asking the user to act upon it. Who would want an app that instantly saves a vcard to their contact list, or opens a url as soon as they scan it?
The mouse has always felt 'different' to me on OSX. I think this explains half of it, the other part being that the hotspot pixel for the cursor isn't actually at the tip, but two pixels down.
