Will do! I should have at least a test video out at some time this weekend. If I succumb to rampant rhythm game voyeurism then I'll probably buy the rest of what I need fairly soon.
I'd say at this point that it depends on the price of cameras. There is a really ghetto way that I can use my phone camera using iOS 8's screen mirroring (basically, mirror the screen, fire up the Camera app on the phone, set it in video mode so that its "shutter" speed stays above 1/30 or 1/60, and crop off the app chrome), but I'd rather not do that. Those cameras aren't really meant to take video for hours on end. I've heard that the PS4 camera is quite nice, so maybe that'll be an option. As a bonus, if it doesn't work out I can always use it for my PS4.
The only real rule is that whatever I get has to work on a Mac. Shouldn't be too hard, though there are a few things that curiously don't have drivers for that platform (such as the lower end Dazzles and such). I don't want to have to unplug my audio interfaces just to do some stupid streaming (I have every port except for the SD card slot in use on that poor thing, not to mention all of the ports on an external USB 3.0 hub).
The other touchy thing is going to be the audio. Obviously I'd like to have both the direct game audio so that the quality won't be shit, but I'd also like to have other audio so that I could talk and so that viewers will be able to hear the key clicks (and me screaming when I fail A [7K] with a 78% like what happened to me other night...I passed it on my next try, at least). I prefer playing audio through the TV so that I can hear the keys more clearly, but I think I'm just going to have to give up and wear headphones. Even if I turn my mic gain down, that doesn't change the fact that I'm using a condenser mic that could pick up an ant farting from two states away. My noise isolating studio cans are out of the question, so...uh, Apple earbuds, maybe? Hell, that would be an improvement over my TV speakers.
Edit: Ran into some complications. The Dazzle absolutely refused to record audio with VirtualDub, and Premiere's capture only works with very specific, presumably high-end devices. I tried pumping the audio through my mixer, but since USB shares an input/output with the 2 Track In/Out, I couldn't record the RCA input with USB.
I have a couple of options, but I'm going to need some more adapters either way. I could ditch USB and use one of my UCA222 interface to pull audio in from the mixer. I'd rather not do that since I would greatly prefer having digital output. Another option is adapting RCA to unbalanced TS connectors and plugging them into the currently-unused ch 3/4. That would probably be the cheapest approach and would still be effective. The problem with these two solutions is that while it would allow me to plug everything into my mixer and monitor it with my studio headphones, I wouldn't be able to do much with the audio in post-production. While I want the clickity clacks from the keys to be audible, I doubt viewers would want to hear them quite as much.
The only real ways to do this while keeping the audio separate is to either come up with another piece of capture software (and I really don't want to use the crash-happy Pinnacle software that the Dazzle comes with) or get a better capture device. I'd rather get the Dazzle working, because I don't want to throw a whole lot of cash at this just yet until I know it's going to work.
I could still technically get the game audio to come through the mixer so that I could monitor it even if I do one of the other two options. I'd have to get another set of RCA splitters, run RCA cables across the room to my mixer, adapt them to TS, plug them into ch3/4, and banish the audio to the alt3/4 output (on my mixer, muted channels are sent to alt3/4, which I have set to come through the headphones).
It's times like these that I'm glad I ended up going with the X1204 instead of sticking with something smaller, like the XENYX 502 or a basic XLR/USB interface with +48V.