I will be interested to see how long this goes before it comes under the gaze of Games Workshop.
I was thinking the same thing. Especially considering what happened over at board game geek where games workshop made them purge all fan-made player aids, expansions, etc for games workshop games.
Then there was the awesome fan-made space hulk pc game that got knixed. Fortunately, the guys who made it decided to re-theme it just enough so they could still release it under the new name, Alien Assault.
The one that really burned my biscuits though was Terror Drome. Not a games workshop franchise, but it ran into the same problem. It was a bad ass fighting game that starred all the famous horror movie icons like Freddy, Jason, Ash, Leather Face, Pinhead, Chucky, Candy Man, Maniac Cop, Tall Man, and Herbert West. All for free and made by one guy (as far as I know). But then he got a cease and desist by the respective movie companies who held the rights to the characters and was forced to remove Freddy, Jason, and Ash. Really sucks.
But, the Alien Assault and Terror Drome situations did teach one important lesson for anyone making a fan-made game based on a commercial license. The LESS media attention, the BETTER! Both Terror Drome and Alien Assault received quite a bit of internet media attention.
I don't think a roguelike would garner that much attention from GW since it's a fairly obscure fan base (maybe not for long though with Dredmor and what-not). Especially if it's ascii. Although the tiles definitely look cool, it will be more likely to draw attention from GW.