I basically want to echo the sentiments of others in this thread.
We also have an ArmA and Teamspeak server, running Linux, sitting in a server room with a 100 Mbit connection almost straight to the backbone. This is the way to do it if you only can. It will be upgraded with the latest hardware as soon as the Linux server binary comes out, but it's been a frustratingly long wait.
I think this is working against Bohemia Interactive as well. From a server administrator point of view I have a suspicion that most big and/or well-established OFP and ArmA servers were run on Linux. ArmA 2 is already pretty stable, but the multiplayer community is really suffering because of this technically minor issue. If you hit the community you also hit the sales of games to come. I doubt many bought the game for the single-player campaign.