Although it doesn't work with GPS coordinates from what I can tell, this 
site would be the next best thing and it uses Google Maps - 
http://www.gmap-pedometer.com/

eg. http://www.gmap-pedometer.com/?r=1430152

Eric F Crist wrote:
> Google Maps?  You may need to do the Pro/subscription version to do  
> the GPS stuff, though.
>
> Eric
>
> On Apr 1, 2008, at 11:18 AM, admin at lctn.org wrote:
>   
>> This summer my parents are going around the states on their bike. I  
>> want to set up a web site that can be updated daily, showing their  
>> progress. Is there a web app that they can key in gps coordinates  
>> that will produce a nice map view of their progress?
>>
>> -- 
>> Raymond Norton
>> LCTN
>>
>>