This has been reported on quite a bit already, so I’m just going to discuss it quickly: Mixbus, an Ardour-derived DAW from Harrison, famous makers of massive analog mixing desks, is now available for Linux. For more info, please check out the excellent posts on the Ardour blog and Create Digital Music.
I’m very happy to see Mixbus on Linux — it sounds like an excellent product. Sonically, Mixbus adds a high-pass filter, EQ, and compressor on each channel, along with four “mix busses” with tone controls, sidechaining, compression, and tape saturation. The real difference, though, is in the workflow: having those simple compressor and EQ functions, and the sends for each of the mix busses, directly at hand on each track lets you dial in adjustments quickly and intuitively, just like you would if you were sitting at a real console.
As someone who still doesn’t have a great grasp on the finer points of mixing and mastering, I could see Mixbus coming in very handy. I might not want to use it as my primary DAW, especially once Ardour 3 hits with is MIDI features, but it would be a simple matter to record all the parts in another DAW, say “it’s mixing time!”, and then dump stems in to Mixbus to make the most of the material I’ve recorded.