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A dock might come out later on, made by a third-party manufacturer, but don't hold your breath. Anyway like Dickr43 said this thing is not really ment for the wall, it's ment to be used like a pronto. You leave it on the coffee table or in its dock on a shelf from where you can grab it when you need it.
That said, seeing how thin it is, I'm sure you can have some small decent looking aluminium slide-in brackets made or something like that and leave it on the wall most of the time without connecting it to the power. If I remember correctly the thing has 1 month of stand-by time so it would probably be fine if you put it in the dock for charging once every week or two weeks. Time will tell...
Should you want to affix it to the wall without a dock/holder uglyfying it, you could just bolt a small plate to the wall and glue the device on the plate, just be sure that it is near to a wallsocket so you can charge it from time to time.
. But learning to do the same things in too many different technologies feels to me like a waste of time, especially if I can do it using the technology I know already. And reading about the Archos also makes me want to get one 
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