As one of Vuo's developers, I work on Vuo's engine (the thing that makes compositions run), work on nodes, and write documentation. You'll see me on the forums answering people's questions about Vuo.
I've been developing apps and frameworks for several years (since I was in college). Pre-Vuo projects include Kineme Quartz Composer plugins, iOS apps for education, an app that analyzes photographs of tomato slices, and software to help people with disabilities use talking keyboards.
I enjoy using Vuo to make live music visuals. My hope for Vuo is that it will grow into a community of people of diverse backgrounds and identities making lots of different artistic, useful, unique, goofy, beautiful, crafty, wonderful compositions.
The Filter Skeleton node passes through the values received from NI mate, except that it negates the X and Z coordinates so the directions will match up between NI mate and Vuo. It doesn't scale the values to a -1 to 1 range or anything like that.
I was going to create a feature request for RTSP support (it's not there as of Vuo 1.2.6), but then my excellent coworker discovered that it only took a small change to get it to work. So that should be in the next major release.
In the meantime, if there's an RTSP-to-Syphon solution that works for your situation (thanks, @jandraka, for the list!), that is what I'd recommend.