I'm sure no one is going to believe me but four days ago I went to the apple store to exchange my 8gb model (bought on june 29th) because I was starting to get air bubbles on my screen, anyways, not too long after I walked out of Apple I got a call from a friend and the first thing I noticed (and my cousin) was the volume of the ringtone, I was still inside of the mall and I had the phone in my pocket and I was able to hear the phone ringing.
compared to the first model I had this phone sounds much louder and better, so much that my co-workers and family were able to tell a difference when they borrowed my phone to watch you tube videos. it's not extremely loud, but enough that for the first time I had to lower the volume of the alarm on my phone, I keep the phone next to my bed every night.
one of my friends just bought an iPhone last weekend, and I got mine exchanged 4 days ago and we both compared our new phones to out other friend who still has his phone from june 29th, ours were definitely much louder,
so I don't know if Apple did a silent upgrade to the speaker, or maybe we're just crazy????