The LFG system in TBC is basically a list of people that have signed up for a dungeon. Once you get a group you don´t get teleported to the dungeon, that´s added in WoTLK.
In TBC you still need to walk (in most cases people will fly) to the dungeon once you get your group. The meeting stones from vanilla are turned into summoning stones. When 3 people are outside a dungeon they can summon their companions much like a Warlock can summon people.
TL;DR: people still need to travel to the dungeon in TBC.