I've spent the entire weekend with the F8500 and VT60 in my living room.
I will say, having spent more time with the F8500 (as I have not ignored it since getting the VT60), it is a great display. The screen uniformity is actually better than my VT60.
As far as blacks, in dark room, they are very good on F8500, but they are not quite as stable or robust. I played a lot of scenes from Castaway, Sin City, Dark Knight Rises, Star Wars (A New Hope), and more Star Trek The Original Series. Both units fed the same feed from an Oppo 103.
It's really kind of weird sometimes. On a lot of material that is really dark, the two displays are so close they are basically identical.
Then there are scenes where brightness enters the image and the VT60 is decisively better evidenced by the letterbox where they are darker on the VT60 and lighter on the F8500. In some of the 4:3 Star Trek materials, it's as the brightness bleeds into the bars where as they are rock solid dark on the VT60. The image will also appear with a bit more contrast in these scenes too, so I do think the better ansi contrast is coming into play here with the VT60. Still, the other scenes they can be very close. If Samsung could issue another firmware to fix the floating blacks (or whatever it is), it would be very interesting.
The ABL effect is real and whites do appear more pure, more bright on certain content (although I don't see the issue arise as much compared to the difference in blacks at times.) There were even a couple of scenes on tattooine with Star Wars this was evident, but also in Castaway where it was more evident on the bright bluish skies and one scene with clouds. Clouds at times could look a little dingy on the VT60 by comparison. Blue skies looked a bit more brighter and pure. Most scenes looked identical though between the two in this regard.
Color is more difficult to comment on given you really need a meter, but I left it at default for Movie mode on the F8500 and THX Cinema on default for the VT60. Seems best for the non-professional. With that said, colors are a bit more saturated with THX mode on the VT60, but again I don't base a ton on that without a pro cal.
Any way, both are great displays to be sure.