R and googleVis - possible to make a “motion map”?

Question

I am typically using R to do statistical analysis, and rather new to the data visualization capabilities. I'm trying to figure out if there is some way to marry the motion chart package gvisMotionChart with the mapping package, gvisGeoMap. I'd like to display a video of events over time, appearing on a map on their date of occurrence at lat/lon coordinates and then fading out. Anyone know if it's possible to do this? Any additional concerns if I have over 50,000 records (daily over 5 years) that I want to feed in to be displayed?

Please note that I do not have to use the gvis packages--I am just using these to motivate the idea. If there are other dynamic mapping packages available in R that will just draw on a shapefile and my event records, all the better.

Thanks!