A Closer Look:
The i7 is a major design change for Intel; so major that they needed to create a new socket to accommodate it. The new socket has 1366 pins as opposed to the 775 of prior processors.
A Page From The Enemy:
Since the dawn of the NetBurst architecture and continuing on into the Core2 line, Intel has always featured a memory controller separate from the actual processor. No longer is this the case. With the creation of the new i7 line, Intel has decided to copy a page from AMD’s book and integrate the memory controller onto the chip. This action alone is one of the key design changes that set the i7 apart from all prior Intel chips. The first incarnation of the i7 ships with a triple-channel DDR3 memory controller, which means that RAM modules will need to be installed in groups of three in order to fully utilize memory bandwidth. With this decision to integrate the memory controller, Intel needed a way for the cores to quickly communicate with the rest of the hardware. The Intel QuickPath Interconnect or QPI is what came out of this. The QPI for the i7 is essentially what HyperTransport has been for AMD chips. It replaces the FSB and offers a high speed channel to communicate with all of the I/O devices.
The Return Of An Old Trick:
Following the new power efficiency model that was adopted for the creation of the Atom (designers may add a new feature to a chip if it yields a 1% increase in performance for at most a 1% increase in power consumption), Intel decided that it was worth the power to efficiency cost to bring back Hyper-Threading for their new line of chips. This means that the first wave release of i7 chips that feature 4 actual cores will be seen by the operating system as 8 logical cores. As to whether or not there is a market for consumer level 8 core processing is debatable, but the fact that the chip is scaling towards the future of parallel computing is quite comforting.