1) The keyboards that can be heard provide a nice window to the dynamics of the song. Listen how the keys build with a big chord and left hand at the end of each half-phrase, and then how it pedals on the B-section. Then listen how during the 2nd verse a little string line appears on top of the chords.
2) Say what you want about Jon Bon Jovi, but he does have some formidable pipes. Especially listen to the key modulation at 3:24, although it does sound like the vocals were copy and pasted in the outro.
3) As reader Justin Freund points out, rumor has it that the outro was speeded up so Jon could hit those high notes, which sounds perfectly plausible by the fact that each chorus of the outro jumps a little bit at the beginning. This is what would happen if it were a tiny bit shorter in length because of the speed change (don't forget this was recorded back in the days of tape before time compression in a DAW).
4) Listen how the vocal develops. The lead vocal is by itself in the verse, a harmony is added during the B section, and then doubled during the chorus.
5) The vocal is pretty drenched in reverb. Although it sounds pretty good, you probably wouldn't find that happening if the song was done today, since the trend is for everything to be drier.
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