Well in theory anyway.
PLEASE NOTE - this is v1.8.1 (the same as Google Play) and not an update to the current app - just an extra way of distributing it.
I received the following from Amazon a short while ago...I didn't specify a "future-availability" date so in theory that means it should be available "today". Not sure when that will be (I think their time-zone is PST so could be several hours yet).Dear Brian,
The following app has been accepted and will be made available for sale in the Amazon marketplace today or on the future-availability date you specified:
Please note that we may conduct additional testing on your app and that the app may not currently be available on all devices.
Although their message says "for sale", the app is free on Amazon as it is on Google Play.
Although my Amazon developer account shows the app has gone from "Under Review" to "Live", I haven't been able to find it using any search terms yet so perhaps it hasn't filtered through the system (I'm hoping that's the reason).
Anyway, I'm winding down for the night. If anyone finds it and successfully installs it then please let me know.
EDIT: It's there now. Direct link is here.