I finally had a chance to sit down and compare the 8xx series against the 78 60". What I found was surprising. The price on the 78 is what it should be, it is definately not worth $500 more than they have it listed for.
1) No Quattron (no big deal but it is newer tech and some say brighter)
2) No USB ports for pictures, videos, anything
3) No builtin WiFi
4) No Ethernet port at all AKA no internet ever
5) No widgets
6) No LED
7) No 3D (this would definatley increase the price)
These are all features that are pretty standard on the units costing $1700 and up (before sales).
In my opinion, and everything I have read - this tv is GREAT for the PQ and for the price, however; if you are looking for something more than just a picture - I would go with the models slightly higher. Maybe not in quality but in fun stuff. Just my 2 cents
In reality - I am still thinking of getting it - the price is so hard to pass up!!!