Matt and Bodhi,
My recollection is there are both bitter and sweet almonds. The sweet variety which is commonly grown has little cyanide in any of the fruit or kernel.
The bitter ones contain cyanide and have a very bitter taste. From my personal experience it would be difficult to eat enough to cause any health issues

I have only ever come across one tree, thankfully.
Bodhi I am surprised that the fruit you have picked are mature enough to have decent nuts in them. We normally leave them to mature on the tree until they split open and release the fully mature nut. I will have to try some premature harvesting to try to beat the birds too. Thanks for all the info guys.