I am having the same issue with my MBP on OS X 10.8.3. I backed up my Galaxy S3 (SGH-i747) with Kies 2.0.0.13023_10 on 4/11/2013... Did a device reset yesterday and went to open Kies so I could restore my old data and BAM! just sits there saying "connecting"... I have uninstalled Kies, reinstalled, rebooted phone, removed battery for one minute (as some posts suggested), then reseated battery turned back on tried to sync with Kies.. Nothing... I have uninstalled and tried to install a previous version of Kies using the techniques that have been posted as a "workaround"... Nothing... I have changed USB cables, as well as swapped USB ports... nothing.... It just sits at "connecting"....... I have attempted Kies over WiFi... nothing... No mater what I do... "connecting"...... The interesting part is, when I disconnect the device Kies actually shows the SGH-i747 in the window as though it was connected. So I get excited and plug it back in and it's back to "connecting".......... It only shows the device when it's disconnected, but only for a very short period of time. And I can't do anything but look at it.