I admit I'm somewhat of a nervous flyer too (like you, I never let it show) and it goes in phases. I'm happy to say that I'm in the lowest phase I've been in ever but that aside the 777 is a great plane and I agree with all the praise the others have already given her. ^
On a personal note, and I know the others will beat me over the head for this, I make sure to touch the outside of every plane I board. Just my little way of letting the girl know I'm onboard and that I appreciate all the cool technical stuff that makes flying so great. I also give her a little pat after every touchdown. It's a superstition and is actually counter productive to my nervous tendencies but after ten years of flying, it's not going away.
Enjoy the flight!