Figured I'd throw my recent EC experience in here with the 777. Flew seat 34D LA-SYD and 31A on SYD-LA.
The flight to SYD was packed and I lucked out that the guy sitting in 34E had amazing control over his bladder. Not sure about other planes but when the seats on the 777 recline, they actually slide forward a bit. So you're not making this massive invasion of the space for row 35. There is power in all four rows located beneath and between the seats. I didn't need to make use of it though. So I have no idea just how much juice you can expect out of it.
The flight back from SYD wasn't packed and I was originally supposed to be in 32D. I got to the airport early and before they even opened the check-in desk, I was able to move my seat to 31A. This turned out to be a very good move on my part!
There is a ton of legroom for row 31 which is great if you're in 31ABCGHI. This isn't so great if you're in 31DEF. If you're in A or I, you can still very easily get out to the aisle without feeling like you just climbed all over everyone. If you're in DEF, you will likely be used as a passageway for those walking laps. Yes, there is a decent amount of space but just by sheer odds, you will have people stepping on you from the looks of things.
The IFE for row 31 swings up from under the armrest for whoever was asking and it is somewhat adjustable. I didn't find it too big of a problem but I had a really good seatmate in 31C to talk to so I didn't have to use it much. 31B was empty and 31C and I made good use of this empty space by opening that tray up once we got airborne and left it that way. We only needed to use our tray tables for the actual meals. Can't say that I noticed the seat being any narrower but I'm pretty trim.
Added recline was very much appreciated and I definitely noticed it. The seats on the 777 do have extending headrests for whoever brought that up. The leg room was noticeable when I was in 34D. The addition of liquor was nice. I can't say I'm all that crazy about the choice of "beers" and wines on Delta. In true FT fashion, I made my best effort to drain the plane of Woodfords. I even got my seatmate on the ride back to join me in my effort. The plane turned out to be VERY well stocked though. (Note: If you're a nice, friendly and outgoing person who can hold their liquor very well, the flight attendants didn't seem to mind continuously slinging them out any time they came by. All the crews seemed very nice to me. I really wish I had status and had fists full of those job well done certs I keep hearing about.)
Er, that's all I can think of for now.