Because we can?
It's a rover thing - you wouldn't understand.
Mike did this once before - he drove Janey from the east coast to the west coast in December 2005. It really captured the interest of many rover enthusiasts who constantly wanted updates and to know how they were doing. It was cold out and Mike was driving it with no doors (not unusual for him) but Janey also was considered "unreliable" at best. Various people would get word of his location and report it to the D90 forums (including Mike's mom) but it wasn't enough.
So as soon as I got over the fact that Mike would rather have his dad (or roverchic even) accompany him on the trip over me, I decided we needed to track his progres and setup a site for everyone to use to follow along.
This is it. Enjoy!