nit: I know not all of PyFarm's code currently follows PEP8 with regards to [import order](http://www.python.org/dev/peps/pep-0008/#imports) but I think code should be moving forward.  Could you order the imports to be:

```python
import os

try:
    from json import loads
except ImportError:
    from simplejson import loads

from utcore import ModelTestCase
from pyfarm.master.utility import dumps
from pyfarm.core.enums import AgentState, UseAgentAddress
```

The main advantage to doing it this way is not just consistency but it also ensures that any possibility of errors occurs from least likely (stdlib) to more likely (pyfarm libs) which makes it easier to debug should problems arise.