A330 / 340 is much quieter than the 777. The 777 seems quieter than the 747 (other than right at the front) but the noise it makes I find more intrusive
The fuselage width of the 330 / 340 seems to discourage airlines from cramming in an extra seat across the cabin, so the very narrow 10 abreast 777 / 747 economy seat is unique to Boeing. (The A320 is also wider than the 737...)
My other beef with the 777 is the icy draught down the back of your neck if you sit in a centre block aisle seat. This seems to be a generic 777 issue, not specific to one air line or engine type.
For passenger comfort, in my experience, Airbus across the range are better than Boeing - though I suspect the 777 has better economics than the A330 / 340. The white 'smoke' (water vapour) pouring out of the air vents when the engines start on hot / humid days and the crackling noise from the ceiling is a bit disconcerting though...
Despite the above, the upper deck of a 747 is still the only way to go.