For those who don't know (shame!), J Allard is, or perhaps was Microsoft's Chief Experience and Chief Technology Officer for the Entertainment and Devices Division.
Primarily he was responsible for Zune and a lot of aspects of the Xbox platform, including Live, various add ons and the overall direction of the system. Most recently he was heavily associated with the wildly-popular "in incubation" product known as the Courier. If Microsoft has a 'Steve Jobs', i.e. someone who put as much effort on design as well as functionality, it would be Allard.
Of course you're aware that the Courier was recently killed off by Microsoft and some of us (well, me at least) thought perhaps it was undergoing a reshaping to make it more consumer-viable (as opposed to a professionally-orientated).
Well, it seems that Mr. Allard has gone MIA at Microsoft and the latest speculation was that he in on sabbatical but has no plans to return. Reportedly the reason: he was none to happy with the Ballmer's decision to nix the Courier, which evidently was past just being a "research project" and had real potential for being picked up for production. True? False? We may never know.
But if Allard has left Microsoft (for whatever reason), dare we say we're pretty crushed as his role and influence in Microsoft, at least from our perspective, seemed like a breath of fresh air. His indirect influence on Windows Phone should be evident from WP7. Lets hope cooler heads prevail and something positive comes from this situation.