[flexcoders] Cairngorm store example - newbie binding question #2

[normc_actionscript]

Thank you Tracy for answering my previous question.

New one:
Why is 'handler' bound to 'confirmOrder' in this snippet?
    <util:Observe
      source="{ ShopModelLocator.getInstance().orderConfirmed }"
      handler="{ confirmOrder }" />     

confirmOrder is a function in the same file.
Is it just a way to set an initial value?

Thanks,
Norm