As mentioned last week, Mythic has been considering the respawn mechanics for the upcoming 1.4.6 patch. Currently, when you die in a RvR lake you will respawn at your keep. There are pros and cons to this approach but it sounds like many players wanted a change.
The verdict is in...
For 1.4.6 you will respawn back at the War Camp unless you died within the Keep Objective area.I never did mind respawning at the keep, but it is not a big deal to me that it is limited now.