What a nightmare for ARRI, this will be very interesting to see what happens when the details come out.
I frequent www.reduser.net almost everyday and I have never seen Jim (owner of RED) act this way, wouldn't be surprised if he goes balls to the walls as far as lawsuits go.
Keep in mind that Jim created Oakley and has been in a ton of legal battles before with companies like Nike and other big ones (sorry I don't know them all). I don't know what it was about but it shows if he is willing to go into litigation with Nike then he is probably going to try to take ARRI down. Just my 2 cents.
Anyway it will be interesting :).