Well, I went ahead and bought it. TotalBiscuit is terrible in that video, but I saw some potential there, so I figured, "Eh, it's just $15." I've played the first nine levels out of 20, and I'm really liking it so far.
Combat:
The combat controls are a bit awkward, but it's kinda like Demon's Souls how you don't just run in swinging like a madman because you have to manage your stamina and try not to get surrounded. I really like the fear mechanic. You can usually fight the enemies one at a time if you use bonfires and the musket to scare the enemies back. And, contrary to what TotalBiscuit said, you can even scare the regular werewolves with fire. You attack with the left click and do the special attack with a right click when you build up rage. You hold Ctrl to use the gun and you right-click repeatedly to reload faster. The amount that enemies fear you is clearly displayed and when their number meets your number, one enemy attacks. You can tell which one is going to attack next because it gets a paw print over its head. Getting too close to them will make them attack even if its not their turn, so it works best to kinda stay back and take them one at a time like an old kung fu movie.
Traps:
You'll spend a lot more time deciding which traps to use and where than you'll spend actually playing the levels. As you can see in the WTF video, you get a number of action points to spend between levels to place traps and other structures like the watchtowers with ziplines. Some traps also cost money, so that's something to keep in mind. On the bright side, traps that cost money and aren't tripped/destroyed stay there for the next level. Almost every level unlocks a new trap and each trap is only effective against some enemies. For instance, a wolf trap will kill wolves but will only slow down werewolves, and will-o'-the-wisps will ignore your firewalls. With the limited action points, limited money, and multiple waves of enemies to worry about, placing traps is a lot of fun.
Skills:
While you're on the strategy layer between levels, you can spend your skill points you get from leveling up and buy new equipment. The skill tree is one of the weakest parts of the game. First of all, you can pick between two guys and it says one is good at traps and the other at combat, but they both have the same skill tree, as far as I could see. The skills are not very inspired. They're like "bait lasts 25% longer" or "reload 20% faster and auto-aim is 33% better." They don't really seem to unlock new ways to play. On the bright side, it seems like you can get less than half of the skills, so you can play a couple times to try out different builds.
Equipment:
Equipment, on the other hand, is interesting. I always want a new gun or a new axe and some potions, but I'm always broke as hell. Also, guns aren't just a progression of better and better guns. Do you want one that has a shitty range but can fire two shots or the one that has a long range or the one that you can actually afford that kinda sux at everything? In addition, you can buy talismans that add to your stamina or fear factor, armor that reduces damage taken, boots that let you run further, etc. You want all these things, but you never have any money, so it makes for some hard choices. The goal is always to save as many AP as possible to cut down trees to get money, so this feeds back into spending more time setting up traps to try to get by on the minimum possible.
Gripes:
Well, the thing I dislike the most is that the brothers don't seem that different. I think one has more HP and the other runs faster. It would be nice if they had different skill trees to give me a reason to play with both guys. Also, there's no multiplayer, so having the two guys is questionable anyway. I'd love to have two-player co-op in this game. The voice-overs are a pain to listen to, but you can skip all the dialogue. As I said before, the combat controls are a little clunky, but you can sort of make due with judicious use of traps.
Conclusion:
So far, I'd say it's worth the $15 I spent. I'll probably play through it two or three times to try out different builds and see how things go. I'm especially curious if I can get the achievement for having $15 at once. I'm on level 10 now and the most I've had at once is maybe $4. Anyway, if anybody cares, I'll post some more thoughts after I've beaten the game or find something about it that turns me off.