Glad this little comparison is useful - thought I'd add a few things I noticed when comparing them side by side...
For some reason, the 5D2's in-camera light meter had different readings for the two lenses at the same aperture - I noticed when using the 85L, a proper exposure reading would indicate a 1/3rd stop faster shutter speed than for the 1.8. I didn't notice at the time, but looking at the photos, you can tell that the 85L's images are indeed ever-so-slightly darker than the 1.8's. Not sure what the reason is behind that, but check out the exif and you'll see what I mean.
I borrowed an 85L a while back for about 2 mins, and I was using a 70-200 at the moment so it didn't seem all that big - but using it side by side to the 1.8 - man, the 85L is a little porker of a lens. Seriously, it's a thick and heavy chunk o' glass and metal. Reminds me of the scene in Jurassic Park where the kid's playing with the night-vision goggles in the Jeep (I hope at least one person gets that reference...) I also forgot that the rear element isn't set inside the lens at all - it sits flush with the back of the lens, inviting grubby little fingerprints to smear all over it.
My initial impression regarding AF is that it's slow - but not dinosaur slow. The 1.8 is quicker no doubt, but hearing what others have said about it, I was expecting it to be a lot slower. I would 't use it for sports, but for weddings and portraits, unless the bride and groom are running down the aisle, I think it'll be the bees knees.
A couple little unique features for the 85L - MF can only be used when it's attached to a turned-on camera, and the focus ring spins very freely, and the hood also spins very freely, independently from both the lens itself and the focus ring. It feels a little weird at first, but it's probably just because all my other lenses have a "normal" MF system and bayonet-mount hoods. These aren't necessarily bad things, but certainly different from other lenses.
Both lenses are pretty sharp wide open, but the 85L is more so. As sharp at the 35L at max aperture, and the colors and bokeh are, for a lack of a better term, pretty bangin'. I'd be outside playing around with it if it weren't 15 degrees right now here in Connecticut
The 85 1.8 is an excellent lens, and for most situations, can do everything you'd want out of an 85mm prime. It's definitely more comparable to the 85L than the 50 1.4 is to the 50L. Bottom line, I haven't had the 85L long enough to say whether it's worth the extra $1400 or not, but it's of superb quality, and I'm looking forward to seeing the images that come out of it in different conditions.