tyzbit made a proposal last week that would allow Ligntning node operators to advertise their nodes using DNS (Domain Name System). Quote:

A challenge end-users face is connecting to nodes with enough liquidity to pay every merchant, and failing that, finding the merchant node in a reasonably sane way to open a channel to them for payments.

As it is now, people find nodes in other people’s visualizers, and pass node aliases around via word of mouth which is very prone to inaccuracy and MITM attacks. A current alternative is attempting to make a payment, decoding the payment request, finding the node on your graph and attempting to open a channel to the merchant. This is only possible if the destination is advertising addresses.