Kind of hard to find information out there... The OP link and links off that page don't lead anywhere useful. Googled around and came up with this:

http://cwiki.apache.org/confluence/display/TS/Traffic+Server

Which also yields:

http://wiki.apache.org/incubator/TrafficServerProposal

http://incubator.apache.org/projects/trafficserver.html

The Apache "champion" is Doug Cutting, of Hadoop fame, so it seems to have street cred.