Since no one else has reported it, the automatic update from 2.0b8 to 2.0b9 fails with the following:
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.000 kernel[0]: QRecall[1016] Unable to quarantine: 93
7/23/15 07:06:47.596 QRecall[1016]: *** setObjectForKey: object cannot be nil (key: _NSTaskExecutablePath)
7/23/15 07:06:47.598 QRecall[1016]: (
0 CoreFoundation 0x00007fff8ee9c03c __exceptionPreprocess + 172
1 libobjc.A.dylib 0x00007fff8cd7e76e objc_exception_throw + 43
2 CoreFoundation 0x00007fff8ed82c66 -[__NSDictionaryM setObject:forKey:] + 1174
3 Foundation 0x00007fff81f5f132 +[NSTask launchedTaskWithLaunchPath:arguments:] + 155
4 Sparkle 0x00000001019f7258 -[SUBasicUpdateDriver installWithToolAndRelaunch:displayingUserInterface:] + 3886
5 Sparkle 0x0000000101a07c73 -[SUUIBasedUpdateDriver installWithToolAndRelaunch:] + 403
6 libsystem_trace.dylib 0x00007fff8e882cd7 _os_activity_initiate + 75
7 AppKit 0x00007fff83541eb1 -[NSApplication sendAction:to:from:] + 452
8 AppKit 0x00007fff83557946 -[NSControl sendAction:to:] + 86
9 AppKit 0x00007fff83557862 __26-[NSCell _sendActionFrom:]_block_invoke + 131
10 libsystem_trace.dylib 0x00007fff8e882cd7 _os_activity_initiate + 75
11 AppKit 0x00007fff835577bf -[NSCell _sendActionFrom:] + 144
12 libsystem_trace.dylib 0x00007fff8e882cd7 _os_activity_initiate + 75
13 AppKit 0x00007fff83555cb3 -[NSCell trackMouse:inRect:ofView:untilMouseUp:] + 2821
14 AppKit 0x00007fff835ae34f -[NSButtonCell trackMouse:inRect:ofView:untilMouseUp:] + 770
15 AppKit 0x00007fff83554366 -[NSControl mouseDown:] + 714
16 AppKit 0x00007fff83abe2dc -[NSWindow _reallySendEvent:isDelayedEvent:] + 14125
17 AppKit 0x00007fff8344dc86 -[NSWindow sendEvent:] + 470
18 AppKit 0x00007fff8344a212 -[NSApplication sendEvent:] + 2504
19 AppKit 0x00007fff83373b68 -[NSApplication run] + 711
20 AppKit 0x00007fff832f0244 NSApplicationMain + 1832
21 QRecall 0x00000001017014d4 QRecall + 5332
)
Of course, manually downloading and installing works like a charm.