my current system:
CPU = i5 2500K
RAM = G.Skill NT 2 x 4 GB
Mainboard = Intel DH67CF
SSD = Intel X25-M Postville 80 GB
OS = Windows 7 x64
the system I'm thinking to build:
CPU = i5 3570K
RAM = G.Skill Ares 2 x 8 GB
Mainboard Intel DH77DF
SSD = Samsung 830 (256 GB)
OS = Windows 8 x64
Afaik the only differences between the CPUs are Lythography (32 to 22 nm) and the IGP (HD3000 to HD4000). Have read somewhere that there might be a heat problem with the 3570K although the die size is smaller (160 mm² to 216 mm²) and the wattage lower (77W to 95W). The SSD 840 Series seems to have a (significant) lower life expectancy than the 830 Series, according to Anandtech.
Issues that I still have with the DH67CF
_ intermittent restart after shutting down
_ BIOS unaccessible via F2
Has the DH77DF any issues I should be aware of?
I was thinking of that as well.
Haswell will need a new socket 1150 and a new design of motherboard.
It's being said that the IGP will have at least 24 execution units. HD4000 has 16 and HD3000 only 12.
Apparently it will be available for desktops much later than expected.
I don't think there's a noticeable difference in performance nor temperature development between the 2500K and 3570K. And neither would 16GB RAM instead of 8GB make any difference as my system utilizes only up to 50% of my current 8GB RAM. Afaik the only differences between DH67CF and DH77DF are a new BIOS interface and quality capacitors. So you're right, a new system doesn't really make sense.
Although I don't expect a big difference, I still plan to get the SSD Samsung 830 (256GB) soon because it will be phased out from November 2012 onwoards to be replaced by the successor 840 Series.
The "Visual Bios" is somewhat worth to upgrade, but " quality " capacitors is not a reason in my opinion.
If you do care it, the Asus " ROG " series and Gigabyte " Sniper " series will be the much suitable choices.
I never use integrated video card so I won't be confused by HD 4000 or HD 5000, I just take it as a backup solution when my NVidia vga card can't work.
Samsung 830 uses TLC memory which I am doubting its reliability, so only I can say is " Good Luck ".