This is great news! I have always wanted to try Dwarf Fortress but I know myself and I know from past experiences playing ASCII MUDs and rogue-likes that I don't play them enough to memorize what the different symbols represent and that inevitably causes me to drop the game entirely out of frustration. It seems like a small thing, but having the graphical version of the game on Linux is a huge win to me.
Doesn't look like so in the beta at least, it will always launch in an SDL window - and doesn't link to the curses libs either, which makes some sense with it being a Steam game.
Though using dfhack and the remote interface could probably still be used to have a tty client.
I've recently gotten into this and it's an amazingly detailed game with so many things to offer/handle it's frankly overwhelming.
A native linux version is amazing and will def wait for the release as I've recently started a look run which is pretty good for me,given my limited experience.