The company behind Angry Birds has reacted with, if not anger, at least mild irritation to Microsoft allegedly using the game’s logo without permission.

The dispute was prompted by the official launch site for Microsoft’s new Windows Phone 7 series, which gets its official unveiling today. In the section detailing the various features available on the system and the applications that would be on the phone, Microsoft included an icon of the Angry Bird game.

Rovio Mobile, the game developers, responded by posting on Twitter: “We have NOT committed to doing a Windows Phone 7 version. Microsoft put the Angry Birds icon on their site without our permission.” It later clarified that while it was still possible that it might release the game on Microsoft’s phones, the real issue was that “we don’t like others using our IP without asking.”

Microsoft later removed the icon and said “It appears information was mistakenly posted to Microsoft’s website, and has been removed.”

That does leave the question of exactly how such a mistake was made. There are at least two possibilities that don’t look great for Microsoft: it deliberately tried to mislead potential buyers, or it was simple incompetence. If the latter is the case, it’s hard to imagine how somebody could have simply picked Angry Birds as a possible game and gone to the trouble of acquiring an icon without thinking twice.

(Legal note: Image copyright Rovio Mobile, used for illustrative purposes only. GeeksAreSexy.net has no connection with the game Angry Birds or its developers. And we didn’t steal any eggs, either.)