Kube

In the new scene inserted into the DVD of Empire, Darth tells the Empire of his plans to bring Luke to the dark side.

That doesn't make sense to me. It seems like he would want to do that in secret. Especially, when they meet, Vader asks Luke to join him and destroy the Emperor.

Seems Vader would have been more coniving if he never hinted at his plans to the Emperor.

Plus the Emperor would have known that Vader - as a Sith - would use Luke to defeat him. Unless the Emperor wants Luke and is now down with Vader and his 1/4 mitoclorian ways.

DthRdrX

The interesting thing is that they are openly talking about breaking the rule of two, and taking Luke as an ally. In secret, they both want to ditch the other but won't do so until they know they have a sure thing with Luke on their side.

Cameron

but anakin also wants padme to join him ruling the galaxy...

Asajj Ventruss, could also be considered a third....but she was not a sith lord, nor was luke...i think the rule of two is only meant to be for lords...