Intel will be launching three new Core i7 (Nehalem) products begining Monday, at 2.66GHz, 2.93GHz, and 3.20GHz, at prices ranging from $285 to $999 (qty. 1,000). That's right: You'll be able to pick up a Core i7 CPU for around $300 fairly soon. Of course, that's not the whole story: You'll need a new motherboard and very likely, new memory, since the integrated memory controller only supports DDR3.
The initial Core i7 CPUs will offer a three-tiered cache structure. Each individual core contains two caches: a 64K L1 cache (split into a 32K instruction cache and a 32K data cache), plus a 256K unified L2 cache. An 8MB L3 cache is shared among the four cores. That 256K L2 cache is interesting, because it's built with an 8-T (eight transistors per cell) SRAM structure. This facilitates running at lower voltages, but also takes up more die space. That's one reason the core-specific L2 cache is smaller than you might otherwise expect.
Like AMD's current CPU line, Nehalem uses an integrated, on-die memory controller. Intel has finally moved the memory controller out of the north bridge. The current memory controller supports only DDR3 memory. The new controller also supports three channels of DDR3 per socket, with up to three DIMMs per channel supported. Earlier, MCH-style memory controllers only supported two channels of DRAM.