Not quite right... most of the seats are the same width, but the centre seats on the A380 upstairs are wider than those on the 777.

If you pick an E seat on the upper deck, you'll get an extra 4 inches of so of width. BA went for the cheap options when updating CW for the A380 (hence the power issues to the dividers) so rather than centering the seat with this extra space, they put it all down the right hand side (as you sit in the chair). So if you're right handed, it's a nice little extra