I've got a MacbookPro running Intel core i5 with OS X Yosemite. So far its been over 20 minutes, and it still shows the Android loading screen. I installed the HAXM extension and confirm it is loaded:
➜ ~ kextstat | grep intel
147 0 0xffffff7f82bd4000 0x14000 0x14000 com.intel.kext.intelhaxm (1.1.1) <7 5 4 3 1>
Here is the avd
profile I am using: