Yes. This issue has been resolved with the OS X 10.9 update, running Minecraft 1.7.2/ Launcher 1.2.8. Thank you for your continued support.
This seems to be an OSX problem. I switched from using the Magic Mouse to a Razer Taipan and it made no difference with the scrolling. And it works perfectly fine on my Windows computer.
Yes, this bug still exists in 0.12.1.