It could mean any number of things. We have a few clients here who are load balancing port 80 requests using the routers (i.e. traffic comes into a public IP address then we use NAT off the edge router to convert into a private IP address). DNS load balancing is really just request splitting because the DNS server spits out a different IP address for the same domain name lookup based on the round robin settings.
There are also lots of goodies that can be used for mail servers - that's a whole new ball game.