I just got them this morning and took off on a 10 mile run on the R.I. Trail on both the paved and unpaved sections. These are definitely a minimalist shoe. Imagine wrapping your foot with a good breathable  material that fits so perfectly it's like a second skin and then coating the bottom where you have ground contact with Vibram rubber. If you have a normal to high arch and neutral stride and have seen your "wet foot print pattern", that's what the soul of this shoe looks like. No more, no less. The heel and mid-foot fit is exact. The toe box area is very roomy allowing toes to move unrestricted as if you were not wearing shoes. This is allowing natural running with minimal bottom of foot protection as you can get. (my 2 cents worth). The Vibram allows good grip on every surface I tried, a little snow, ice, mud, and standing water. I had one of the best runs I've had in along time (not counting running barefoot on Daytona Beach this winter); it was just plain fun. I like them and recommend trying if you like less shoe and more you in control. 2 suggestions: DO NOT wear socks (they will restrict forefoot and toe movement), and get them at your true size. You won't need the extra room up front. I'm an 8.5 and usually get size 9, but, these fit perfectly in 8.5 One other suggestion, learn proper stride; these are not for heel strikers. Adam White gives a very good description of good running mechanics.  

I've got about 100 miles on mine and really like them. I would not recommend them for trails with a lot of rock as you can really feel them, Farmdale is about as much rock as you want to tackle with them.
 
At Jubilee they are perfect as there are little to no rocks there.
 
The toe protection is as good as most trail shoes and water sheds right out of them.
 
I wore them for a couple of weeks as everyday shoes to get used to them before running.
 
Then I ran 3 miles in at Jubilee. My calves were sore for an entire week. What was strange though was since then my calves have never been sore(no more then normal ramping up) since.
 
These shoes certainly change your running style and I think I'm still working harder on a run with these then with a "normal" trail shoe, if that makes sense.
 
I really like these shoes and am looking at other Merrell products as well.
 
My 2 cents.

Great article, great advice, thanks!!

I think Yank blazed half of the trails out there...