Golden Balls, the opening words to your post are wrong. The Etihad may well be a fairly nice looking stadium, we are very lucky to have it and without it we wouldn't have the Sheikh; but it is not a fantastic stadium. I'd go as far to say its a bit shit as far as being a proper football stadium goes.
Also it's the fifth highest capacity in the league, not third (Old Trafford, Emirates, Sports Direct, Stadium of Light are all bigger than ours).
It's a symmetrical stadium that doesn't lend to any individuality in any stands ("We are the South Stand" - so fucking what, you're half a stand where the other half [away fans] are louder than you, your name is bland/shit, and there's twice as many Blues down the other end!). The tiers are too small therefore separating fans into small chunks here and there. We have about 3000 seats (standing area) for vocal fans which is utterly woefully pathetic - I could name twenty+ clubs that have more than that, even Stockport have more than that as a vocal stand. It's too nice, people sit back, relax and watch the football in - for many - absolute silence every single week. Its like we have three main stands and one noisy end which is half and half [home and away]. When we play at home in the cups we have to move our already too tiny vocal area to house a fucking mass of away fans - this is APPALLING! - imagine the Kop or Stretford End having to do this?! The away fans get pride of place and it looks like there's about 10000 of them on tele. The roof is so high up and points out to the sky so any atmopshere is lost upwards. Etc...
I can remember all our good atmospheres since we moved there (Chlesea, their only loss in 04-05, Villa Saturday tea time win in 04, the first derby there 4-1 in 04 and Hamburg which was good but not as good as is looked back on). Ask a Spurs/Stoke/Derby fan the same question and he'd name you that many a season at their grounds.
People in the vocal areas think we have a good atmosphere - ive stood over in both and thought the same - but away from them areas it sounds like a murmur in the corner most of the time and anytime an away team brings a full allocation they almost always out-noise our vocal areas. I watch back every game, win/lose/draw, on Football First and Sky+ and rarely do you hear a good atmosphere coming across on the tele.