Carradice: I would love that too. I guess that Mage might be the system to use for games happening in the present day, whereas Ars Magica would be the one for Dark Ages. However, Ars Magica can be held as the most ambitious game. "Downtime" management of covenants, and the companions and grogs. Not to mention the rich setting.
No idea about the computer Ars Magica game that you mention.
mqstout: Black Chicken Studios. On looking again this morning, it looks like the Ars Magica game was cancelled during development. (I plan to try these games, including this release, when I get time.)
They also started another series based on Werewolf. There was a demo for the first game. It is fun to play, the player starts in the shoes of a foreign girl who visits Bialowieza forest and is confronted with her heritage, of which she was not fully aware. Nice RPG.
With all these games, I agree with you that an Ars Magica roleplay videogame would definitely be made. Also, there is ample room for a strategy/rpg game with covenant management.
Not the same and I have not played it yet, but
Unavowed, an adventure game about modern day Wadjet Eye about modern day mages (the titular unavowed) seems enticing.