All versions of the game (Loki, Bungie win, Bungie mac) use the same game data files and are completely file and network compatible with each other. The only difference between the different platform distributions is the binary executable file. What we are beta testing here is a native Linux executable version of 1.7.2.
Also, granted you access to the private testers forum. Linux beta thread here: viewtopic.php?f=9&t=5450