I haven't listened to any of the commentaries on PotC yet, but I did peruse many of the other extras. First off, you know how most of us are flabbergasted when we hear a movie cost a hundred million dollars to make? I get it now. When you watch the 'Making Of...' stuff, you understand where all the money goes. (I hate to think how much the sequel will cost with Depp, Bloom, and Knightley I'm sure all getting hefty raises.)
Secondly, I also understand why most of the nineteen deleted scenes got cut. Actually, they were less scenes then additional parts of existing scenes that served no purpose or added nothing. Without spoiling it for those who haven't scene what was cut, I will say there were three scenes between Jack and Elizabeth I wished had been kept in. Not only did I enjoy seeing the additional interaction between the two, but the interplay added depth to both characters.
Now for some thoughts on the commentary for 'Serenity'
As I suspected, the commentary gives us hints at what might have been had the show continued. (Insert sobs here.) Some revelations were small such as there is a large tank underneath the floor of Serenity. In Episode 16 one of the characters was to run through the ship then dive into it.
A larger revelation was discussed as the crew wanders through Persophene. There are Blue Sun signs everywhere. This was to be a major plot point later in the series. Joss was still working out the details but he envisioned Blue Sun as some huge conglomerate with ties to the government and with a major connection to the show's underlying mystery. (Two by two, hands of blue, anyone?)
I was also interested to hear Joss draw comparisons to Buffy. Kaylee was the equivalent of Willow - the heart and soul of the ship. If Kaylee trusts someone they are to be trusted. If she believes everything will be OK, then it will.
Jayne is Cordelia (interesting mental image there ;), saying what everyone else is thinking. Joss also commented that Jayne had a crush on Kaylee. Huh? I never picked up on that though there were apparently several moments that point to it.
Other points of interest....
Inara was originally played by Rebecca Gayhardt (sp). Joss went so far as to shoot footage with her even though he knew she was going to be replaced. All he'd say was that her "energy" was wrong.
Joss was to have played Badger but changed his mind.
Nathon Fillion seems to have the same enthusiasm as James Marsters does for Joss and his work. Though, Nathon seems to have a better understanding of his character. ;)
And one thing I overlooked upon previous viewing was how quickly Book overpowered the cop and easily disarmed him. Another sign he was more than just a Shepard.
Joss is a talented writer. He can also be incredibly bitchy. I want to hear about 'The Train Job' not how FOX screwed you over every thirty seconds. Yes, what they did to the show was a travesty. They botched both the development and marketing. I don't need constant reminders like 'and here we need to introduce so and so who was introduced in this manner in Serenity which you didn't see until the end of the series because FOX made us reshoot the pilot because blah blah blah..." I get it already. You also had seven years of Buffy and, so far, five of Angel. Most writers don't ever experience the freedom and success you've had. Worry about what might still be instead of whining about how FOX done you wrong.