[...] 1) How will mods be affected? A lot of work went into ALL of the mods that you can find on Starsiege: Tribes today, and Garage Games shouldn't force these modders to go through a lot of trouble just to get their server up and running again. [...]
Q: I heard from [here/there/somewhere], speculation that mods would not be supported, is this true?
A: From the beginning of this project a goal has been to make sure that mods are not sacrificed. Mods may need to adjust a few things here and there to work with the new base game scripts with the new version, but should work with relatively small amounts of fixing up.
Q: What if my mod needs to have custom art or data downloaded to the client.
A: There are no immediate plans to directly distribute them through the site, so we may have to filter them from the server list for players that are in browser. Luckily most mods don't require extra art and files. We may selectively seek the permission to release a community made resource through our website from the author, at our discretion.
You can find more info about modding and the changes to the game in the first post.
I DEMAND OPEN BETA
In other words: when is the open beta coming out?
You expect an open beta for a game from 1998? For your question about "when": Read the first post.