The current lag is making group formation for quests and dungeons extremely difficult. Whispers and group invites are taking up to five minutes to process. In that time, the players being invited frequently complete the quest or join another group, which forces everyone to start the process over again. The only reliable workaround right now is forming a full group entirely within the guild. I sincerely hope this is resolved before launch; otherwise, the game will be unplayable for most group content.