Looks like Apple's changed how the Personal Hotspot works in iOS 5.
The network will not be visible to ShutterSnitch (or any apps) until a device connects to it.
Now, since they've changed something, the current version (2.1.8 and the upcoming 2.1.9) won't detect the network once you enter a collection, and will tell you that there's no network connection ...although that's not actually true. So ignore that. There's a connection, and you'll be able to transfer photos. It's actually just a "visual bug". I'll be submitting version 2.1.10 that knows about the new Hotspot type, after 2.1.9 is approved.
You're problem right now, would be to find out what the iPhone IP is (the IP that you would normally see in the "Listening info"). On my phone it's 172.20.10.1 - it's probably the same on your side, so try that. If that's not it, you can try joining the iPhone Personal Hotspot from a computer and notice what the IP address the computer gets on that network. The iPhone IP will then be the same, but ending on .1
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