Memory bus in Core i7 processors

It's been a while since my last PC build and I'm confused about the new memory architecture that is integrated in Intel's Core i7-processors.

Core2Duo's had a Front Side Bus speed, for example 800 MHz. For dual channel memory (DDR2), it meant that the FSB speed was a bottleneck. However, now the new Core i7-processors don't have a FSB but instead they somehow deal with RAM independently. Can someone explain how exactly does this work and how this affects on three channel memory (DDR3)? Is there a bottleneck like there used to be with Core2 processors?

 

QPI

http://en.wikipedia.org/wiki/Intel_QuickPath_Interconnect