Yes, or at least that's the plan.  For example, when I simulate a failure in a task I get:

```
$ aws s3 cp /tmp/file-0 s3://jamesls-test-sync/
upload failed: ../../../../tmp/file-0 to s3://bucket/file-0
Simulated failure!
```

I believe there's a missing `result_queue.put` for the `UploadPartTask` class, I'll go ahead and update.