Hey Castlebridge---
To really see something interesting in real-time, check out this METRO site besides the one you listed :
1. Go to : [
www.kingcounty.gov]
2. In the middle of page under "Transit & Traffic", select "Bus Tracker".
3. You can choose the TRACKER by either location or MAP.
The route symbols representing the buses move around the map with the route and current time shown in each symbol. Downtown Seattle is first displayed, but you can go to other areas as well.
Cheers.
KRK