Drag-and-drop copying does not work on Macs at the moment - Google's "Android File Transfer" program for Mac is currently broken on some (if not all) Android 4.x phones. Not clear if this is a problem with Android 4.x, Samsung, or OS X, but I can confirm that it doesn't work between my Note 2 and either Lion or Mountain Lion - and my Googling suggests that the problem is universal.
Using 'camera mode' doesn't work either - iPhoto sees the phone but won't transfer files correctly.
Samsung do their own Sync program ('Kies') which sort-of works, but is clunky and tempramental - but it will sync music (sort of).
Older versions of Android supported 'USB Mass Storage Mode' which worked with anything, but in recent versions they've completely replaced this with 'Media Transfer Protocol' which Windows does natively but required the Android File Transfer program on Mac.
The saving graces are:
1. Syncing files over the wire is so last year - there are all sorts of cloud-based options.
2. The Note II takes a Micro-SD memory card which you can physically plug in to a mac via a USB adapter & drag files to it (I haven't tried it yet but I don't think there's any way they could have messed that up).