Firstly I myself run a fanless overclocked lite-gaming pc, used for photoshop/AutoCAD/PVR/MS office/low dpi games etc - would I recomend a fanless pc no, would I recomend a near silent single fan pc - YES.
silent = no moveing parts = major cooling nightmare, hassle and cost.
Just one quality fan running at 5v or 7v saves you so much hassle/redundence it's untrue.
Option 1 - use a heatpipe cooled case - Zalman TNN or Mcubed. (over priced but easiest option as long as your house isn't at +30c most of the year)
Option 2 - use a passive watercooled system (what I have) Zalman Reservator / Cape Corra / Konnect-o-matic. (might be more hassle than your looking for)
Option 3 - use a quality midi tower case with a single fan.
The zalman zm-600 is a very good choice but you shouldn't hit 150w load so it's major over kill.
i7 = hot = noise, so your right it's not really a good idea for quiet pc's.
For duel cores intel is still king - and you (infact most people) don't 'need' a quad. Hot and power hungry both working againest a quiet build.
If your into Overclocking the E5200 is a steal at £60, easily hits 3.4/3.6 and above with low volts and temps.
If not then the E8x00 win both in terms of more cashe and stock speed.
This is my
log of what a nightmare/enjoyable build a passive watercooling rig (with young children in the house) can be
I'm rebuilding that system at the minute (to acheive sub 100w at load @3Ghz) but it's shows my bias and some of my personal knowlage base
P.s. my raptor is near silent - it's in a GUP Japan Smart Drive 2002C that been watercooled and bungee'd

And check out SPCR - loads of excerlent advise and a forum of quiet pc owners (even they don't recoment complete fanless)