Meph - I love DF for just the reasons you linked. It's so... devilish, yet hilarious to invent a mine-cart-baby-splatterer. I mean, who the hell thinks up these kinds of things?!
As for the video series, I can't watch at this moment, but I'll say safely - if you want people to watch (hard enough as is, due to DF's rather niche population compared to much larger games), is to make sure your game is unique, fun, and interesting (I.E. horribly unfair and brutal, lots of death and madness for you, and invaders alike). An example of 'hell' would be to embark on a undead, evil biome with many nasty critters (Nightmares, Giant Gargoyles, barghests, all the FUN critters), all sieges on max with 200+ civs (to ensure non-stop fights and carnage), then dig down at your 4 map corners, straight to hell (takes a good bit of work to do that part right
), and all 3 caverns. This lets all 3 caverns+hell pour to the surface. And for added fun? Make sure the map has thralling clouds too.
Now that? That'd be fun to watch, if done without 'boring defense' (Walling in and using bridges to hide infinitely). I've done a map similar to this. Absolutely maddeningly ruthless, but the funnest fort I've ever done. Mind you, I lost it like fall year 1 due to my migrant wave happily spawning RIGHT inside a damn thralling cloud. I had my defenses designed to put down undead and keep them down - not expecting thralls yet... fun none the less!
As really, watching df for non-df players is boring. The visuals are 'alien' to them (and for the graphic kiddies, unappealing in all regard), and DF really isn't a 'fast, exciting game' - it's quiet for 90% usually, then 10% crazy-carnage-death-sock-beating-fun. Many people lack the patience to wait for that 10% as well. So you need to... encourage it, to keep things exciting as much as you can to have any real hope of viewers coming to watch.