1. downloaded MusicBrainz Picard 1.3.1 dmg ; copied to Applications
2. upon launch the application crashes. The report begins with:

   Process:               MusicBrainz Picard [10435]
   Path:                  /Applications/MusicBrainz Picard.app/Contents/MacOS/MusicBrainz Picard
   Identifier:            org.musicbrainz.picard
   Version:               1.3.1 (Picard 1.3.1)
   Code Type:             X86-64 (Native)
   Parent Process:        ??? [1]
   Responsible:           MusicBrainz Picard [10435]
   User ID:               501
   
   Date/Time:             2015-01-06 09:26:31.099 -0800
   OS Version:            Mac OS X 10.10.1 (14B25)
   Report Version:        11
   Anonymous UUID:        272DBD7D-CA68-9D39-D9D8-A67578BB05D0
   
   
   Time Awake Since Boot: 330000 seconds
   
   Crashed Thread:        0  Dispatch queue: com.apple.main-thread
   
   Exception Type:        EXC_BAD_INSTRUCTION (SIGILL)
   Exception Codes:       0x0000000000000001, 0x0000000000000000
   
   Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
   0   org.python.python             	0x000000010482445f PyGC_Collect + 127
   1   org.python.python             	0x0000000104824e13 _PyObject_GC_Malloc + 213
   2   org.python.python             	0x00000001047bf478 PyType_GenericAlloc + 57
   3   org.python.python             	0x000000010478eb50 PyDescr_NewMethod + 69
   4   org.python.python             	0x000000010478ec40 PyDescr_NewWrapper + 34
   5   org.python.python             	0x00000001047c1132 PyType_Ready + 365
   6   org.python.python             	0x00000001047af046 _Py_ReadyTypes + 548
   7   org.python.python             	0x0000000104812381 Py_InitializeEx + 395
   8   org.musicbrainz.picard        	0x00000001000024ac 0x100000000 + 9388
   9   org.musicbrainz.picard        	0x000000010000117a main + 650
   10  org.musicbrainz.picard        	0x0000000100000be4 start + 52
   
   Thread 1:: Dispatch queue: com.apple.libdispatch-manager
   0   libsystem_kernel.dylib        	0x00007fff88d9122e kevent64 + 10
   1   libdispatch.dylib             	0x00007fff81d86a6a _dispatch_mgr_thread + 52
   
   Thread 2:
   0   libsystem_kernel.dylib        	0x00007fff88d90946 __workq_kernreturn + 10
   1   libsystem_pthread.dylib       	0x00007fff884de4a1 start_wqthread + 13
   
   Thread 3:
   0   libsystem_kernel.dylib        	0x00007fff88d90946 __workq_kernreturn + 10
   1   libsystem_pthread.dylib       	0x00007fff884de4a1 start_wqthread + 13
   
   Thread 4:
   0   libsystem_kernel.dylib        	0x00007fff88d90946 __workq_kernreturn + 10
   1   libsystem_pthread.dylib       	0x00007fff884de4a1 start_wqthread + 13
   
   Thread 5:
   0   libsystem_kernel.dylib        	0x00007fff88d90946 __workq_kernreturn + 10
   1   libsystem_pthread.dylib       	0x00007fff884de4a1 start_wqthread + 13
   
   Thread 0 crashed with X86 Thread State (64-bit):
     rax: 0x000000010009d450  rbx: 0x00000001000ba300  rcx: 0x0000000000000007  rdx: 0x00000001000b81b0
     rdi: 0x00000001000b8180  rsi: 0x00000001000b81a4  rbp: 0x00007fff5fbfd540  rsp: 0x00007fff5fbfd490
      r8: 0x000000000000005f   r9: 0x3682d0f246257b48  r10: 0x000000000000005f  r11: 0xfffffffffb87cd90
     r12: 0x0000000000000000  r13: 0x000000010489af40  r14: 0x0000000104885c20  r15: 0x0000000000000000
     rip: 0x000000010482445f  rfl: 0x0000000000010206  cr2: 0x00000001048c6008
     
   Logical CPU:     10
   Error Code:      0x00000000
   Trap Number:     6
   
   
   Binary Images:
          0x100000000 -        0x100009fff +org.musicbrainz.picard (1.3.1 - Picard 1.3.1) <FFD751CA-37B6-3FAC-9CF0-413E01DAA81D> /Applications/MusicBrainz Picard.app/Contents/MacOS/MusicBrainz Picard
          0x104774000 -        0x10487fff7 +org.python.python (2.7.9, [c] 2004-2014 Python Software Foundation. - 2.7.9) <B39E8AE7-E429-3630-8117-B86F3725C68F> /Applications/MusicBrainz Picard.app/Contents/Frameworks/Python.framework/Versions/2.7/Python
       0x7fff68d9e000 -     0x7fff68dd4837  dyld (353.2.1) <4696A982-1500-34EC-9777-1EF7A03E2659> /usr/lib/dyld
       0x7fff80928000 -     0x7fff80a1cff7  libFontParser.dylib (134) <506126F8-FDCE-3DE1-9DCA-E07FE658B597> /System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/ATS.framework/Versions/A/Resources/libFontParser.dylib
   
   
   

I looked to remove ~Library/Preferences/com.musicbrainz* as suggested in http://tickets.musicbrainz.org/browse/PICARD-647 but I did not have it. I have not run MusicBrainz Picard on this computer, though I have run it successfully on other OS X Yosemite machines.