Is this ready to move out of beta now? What do I need to do - can someone vote it up or something? Thanks...

Thanks. I guess someone else needs to agree it - I can't.

I have done as you suggested. This has been good practise at defining requirements! If it's good to go now, can you mark it as such?

This is why I wasn't made CEO of Microsoft! ;)

I've written a much larger test now: maybe it's enough. I've also copied the test to the example fixture in order to both provide a clear description of what's required and save some work for everyone else.

Good catch on the JSON.stringify and thanks for the formatting tips: I'll have a think about the custom function to check it - maybe that should be a second Kata!

I seem to have broken everyone's solutions. I hope this isn't a fault in mine. I am a bit of a noob when it comes to Javascript and so find it hard to follow the incredibly concise solutions some of you have submitted but I will try and work out what's changed when I have time.

OK I've been more explicit in the description now. Hopefully it is clear now: I will have a fresh look in a couple of days and see if I can spot anything else. Thanks.

Thanks: I agree with you about the object/JSON string ambiguity and have updated accordingly. The test fixture now has a case in it. I had thought that the format of the JSON object was made clear in the test fixture - do you think I should explain in the description too?

Sorry about that: the example probably didn't make it clear enough so I have now specified explicitly. Let me know what you think.