I use the built-in speakers all the time (every day on a number of calls). I will listen to music on the built-in speakers rarely, as I usually use the iPad or MBP for that, but it's still nice to have satisfactory speakers.
The motivation that people have defending the Air is really something. What is happening now is what many of us ("haters") expected would happen, and that is people coming to realize one or more of the drawbacks of the Air and not willing to compromise for a thousand dollar phone.
These snarky replies are hilarious. You have direct accounts of a long line of people, forum members, returning their Airs because the compromises are a bit much for them (as was always going to be the case, because common sense), and you can't help but post smartass replies like this. These are not assumptions / optimism / skepticism, these are people who have these phones in their hands, they are using them and many are returning them.
If all of us who were doubting the value of the Air were labeled haters before the phone was out in the wild, what do we call this - people who cannot come to terms with the fact that no, the Air is not in fact the end all be all because it has too many compromises (which was evident from the start)?