If the Group Finder is implemented it must have cross-server option at least. To those who believe this destroys the "community" should know they are in fact mistaken.
As it stands now, numbers on all but a few servers, even during peak times, are somewhat low. I rarely see triple digit populations on any world, even the space stations, on either server I play on. For a while I was doing flashpoint runs fairly often, say 2-6 a day, but recently that ability has all but vanished. This has caused fewer and fewer people to even log on during non-raid nights and in my guild that has lead to some people just disappearing. The result is, we went from clearing at least 8 man hard mode EV each weeks and sometimes 16 man during January/February, to not even being able to get an 8 man reg EV come March. People weren't g-quitting, they just weren't on as much.
My point is, A cross-server LFG helps the community by giving more players consistent access to group content. Sure you're going to have the jerks who are cruel and rude, but for the most part the groups are fine. The only real problem I can see is ninja-looters. The fix for that is a simple one that several MMOs have employed, restrict who can need for an item. This means a Sith Juggernaut cannot roll need on a cunning based piece of armor for his companion, but he could still roll greed. In the end, if the LFG tool isn't cross server, its usefulness will be limited and will be scarcely more useful than the current LFG system in-game.