There was a lot of talk about the Swift Piksi RTK GPS mid-last year. The last thing I can find is that drivers were included in the ardupilot firmware such that it supported the Piksi as a normal GPS, but as yet without RTK functionality.
That was 6 months ago now, but I can't find anything in any change logs so suggest the RTK support has since been implemented.
Does anyone know anything more about this? It would be super cool to see RTK functionality on this system.