Probando googleVis

library(googleVis)
AndrewGeoMap <- gvisGeoMap(Andrew, locationvar='LatLong', numvar='Speed_kt',
                          hovervar='Category',
                          options=list(width=600,height=300,
                          region='US', dataMode='Markers'))
plot(AndrewGeoMap)
print(AndrewGeoMap, file="~/Dropbox/Public/AndrewGeoMap.html")

Se hace con <iframe width="100%" height="80%" frameborder="0" src="http://dl.dropbox.com/u/2712908/AndrewGeoMap.html">
</iframe>