I'm sort of a "map junkie". Here are some animated maps that I've created in Vegas using tracks created in Google Maps and imagery from Google Earth. I believe that it overcomes a major shortcoming of other approaches that require the user to "draw" the track either with a mouse (E.g. Heroglyph) or by entering "waypoints" (E.g. Route Generator). From the examples, especially the second along the Mosel River, you will see that it would be very tedious to "draw" these. Furthermore, no keyframing in Vegas is required. It does require Photoshop which is probably in the toolkit of most editors anyway.
So how does it work? In a nutshell, here are the steps: 1) Create a track in Google Maps, export as a KML file and then open in Google Earth; 2) compose your imagery, make copies with and without the track visible and open in Photoshop (actually Copy in Google Earth, open new file in PS, and then Paste) 3) make a selection in PS of the track using the Magic Wand tool; 4) create a new layer from that selection and paint the Track (in the example, a red track) using the Brush Tool; 5) create another layer from the same selection and make a gradient using the Brush Tool; 5) export from PS 3 PNG files: imagery only, track only, and gradient 6) in Vegas, import the imagery only and track only PNG's, the track only being on top; and 7) finally, apply the Gradient Wipe transition to the Track Only event in which you specify the gradient file created in PS. That's it. The length of your transition will determine how quickly the animation track moves.
So how long does it take. As a test, I created a route from from Port Angeles to Seattle. From the time to open Google Maps to have it working in Vegas--10 minutes.
If anyone is interested, I would be happy to provide the details of the very sketchy nutshell overview. I must admit that I didn't create this approach on my own. It is based largely on the following YT tutorial that I found yesterday on Line Animation in Vegas. In the tutorial, the author creates the track within PS using the Pen Tool, pretty much like others. My twist--rather than creating the line from scratch, I begin with making a selection of the track created in Google Earth, and then pretty much follow the procedure outlined in the tutorial. In any case, it seems to work well and is relatively quick.
wwaag