Well lower power consumption also equates to less heat, which is important to me. Combine this with the far superior turbo function in the Lynnfield processors and it makes an interesting comparison...
Basically, I'm ditching water to go back to air and am also fed up with overclocking in general. If I went for an i7 920 then I'd have to clock it up to 3.2/3.4Ghz to get the performance I want/need for games and so on. The problem is this means that, the other 90% of the time, all four cores are sitting there, overclocked, sucking power and producing heat, which I need to cool without spending a fortune and/or making loads of noise.
Contrast with a Lynnfield solution where I can leave the processor at stock settings and allow the turbo-boost to overclock as necessary when only one or two cores are in use. Combine this with far better power efficiency due to its improved ability to shut down inactive cores and it becomes more attractive to me.
Ironically it transpires that, to get the features I want, the 1156 motherboard will probably end up costing just as much as a 1366 one would. If I ended up going with an i7 860 over an i5 750 in order to get the hyper threading functionality then I'd wind up spending pretty much the same as I would on a 1366 platform, yet I'd still choose the 1156 for the reasons given above
One final question mark hangs over what processors will be available on these platforms in the future. If 1366 is being positioned as the high-end/server platform then it's entirely possibly that only the very top end processors will be released on this platform, with all the maintream ones being on 1156. Remember the processors are very different on these platform, with Bloomfield having a triple-channel memory controller whilst Lynnfield has on-board PCI-e. Simply making every processor available for both sockets isn't going to be financially viable so they'll have to make some choices. The LGA1366 platform looks attractive now solely because of the i7 920, which is an overclockers dream, but there's no guarantee there'll be any more bargain chips like this for LGA1366 in the future. Only time will tell.