It's official: we here at Velocity USA have extrusions in hand and will be shipping our new double-wall, 45mm rim by early September: http://twentynineinches.com/2013/07/...s-mid-fat-rim/
Projected weight for a 29" rim will be under 700g, with 29 & 26 options in 32h. Black and polished to start. Questions? Ask away!