Meet the Pyro is a pretty good video, but not as great as Meet the Medic or Meet the Spy. It lacks a narrative.
Pyrovision is silly, but you don't have to use it, so everybody wins.
SD_Doomsday is tons of fun. Short games that would be good for competitive competitions. I've never seen a single game become a camp-fest. Every class has a role, but none are too powerful. (Heavy is very good when he gets on the lift.)
The new weapons are a big miss for me.
The Baby Face Blaster is OK, but starting out slow and being unable to jump are too harsh. Once you get going, it's pretty cool going at such crazy speed.
The new pistol is boring. I do approve of things that give fire vulnerability, though. Inch by inch, the Pyro becomes less terrible.
The new Sniper Rifle isn't much of anything. If you get some kills, you get a mild boost to your snipe speed. Less bodyshot damage. Not very interesting.
Cleaner's Carbine seems better than it is. I imagined being able to chain kills, or at least being able to get a kill with the crits, but it's very difficult to do much with the new SMG even when you're critting. If you get up close, the other classes are better than you. If you're far away, the Carbine will just miss.
The Beggar's Bazooka is actually quite fun. You really have to plan ahead to be effective. The major downside is the initial delay. When you press the button to fire a single rocket, you have to wait through the loading animation to fire anything at all. Despite this, the damage potential is huge if you time your attacks right. Being able to fire three rockets nearly at once can wipe out most classes.
The Scorch Shot seems incredibly weak. It does much less damage than the flare gun, and can't get the crit bonus on flaming targets. The knockback is nice, but doesn't justify a huge loss of damage. The taunt makes up for it though. It's amazing.