I give it that dual status because well we don't really know for sure if it's just a compendium with a few extra rules, or a whole supplement with new rules, and scenarios etc.
They seem to indicate it's more on the supplement side, BUT until I get it in my hot little hands, I can neither confirm or deny.
The article also confirms that; "So yes, now you can paint your Stormravens blue, yellow, black, or any other colour that you like..." which is good news for all Astartes players in general.
There also seems to be some hidden asset type rules as well; "There are even special manoeuvres that can be taken by pilots, such as the brutal Dark Eldar slash attack, the Necron firing protocols or the aptly named 'Smash 'em' for the Orks, which essentially results in a mid-air collision."
Also confirmed is the inclusion of material from the Crusade of Fire book as well. The article also goes on to confirm the exclusivity of the product as well, stating; "it's worth noting that you won't be able to get it in stores, so if you want it you'll need to.." (order from the site).
So where do we go from here? Well I imagine that players, while skeptical, may yet be excited at the prospect of new rules. Games Workshop I would think will take a very close look at these numbers and perhaps adjust and duplicate the results if it suits them, and I can still see where store owners will be upset over them getting the big snub as well.
Regardless if you don't have any of these flyers because you couldn't use them before, beat the rush now!
Get your orders in for Stormravens, and Stormtalons before everyone else does!