So I assume because its not happening that there's a valid reason but I was wondering whats holding back the latest builds of DF from being released daily via torrent?
I mean, I don't want to suggest any dissatisfaction with the massive number of bugfixes that cool awesome people have been working daily to fix...
Your post seems to imply some unfamiliarity behind the way DF happens. The "studio" is precisely two guys, only one of whom is technical; Toady One does all the code, all the design docs, all the systems engineering, all the bugfixing, all the internal IT work, all the building, and so on; he's also responsible for a good fraction of the creative work, which is partly shared with his brother along with things like doing the financial statements and the donor rewards. Most of their IT infrastructure is in their apartment.
Until quite recently, it wasn't unusual for the game to go months, and in some cases years, between releases; much of the intervening time the code was "up on blocks" and not compilable due to major rewrites of underlying structure. The build process took about a full day, during which coding, bugfixing, etc. wasn't happening. Our understanding is that recent improvements have gotten the build process down to "a few hours", but that's still time not spent fixing bugs or writing new features. With the exception of rare "hotfix" releases like 0.40.08 to 0.40.09, weekly seems to be a reasonable tempo; much more often, and he's wasting more time building than makes sense.
Now, in an ideal fantasy world, having an automated build farm and modern version control that did all that at the push of a couple of easy command lines, and did so away from the computer you're working on (and outside of the un-airconditioned apartment you're trying to sleep in), might result in updates more often *some* of the time. But that takes a considerable amount of time to set up and even more to learn; and non-negligible resources to keep running.
I'll also point out again that this is an *early* alpha, well under half feature complete. On a normally paced game studio, we'd probably be at least a year out before the first horribly bug-ridden NDA-required closed betas. The fact that the game is playable at all is *astounding*; most software wouldn't even run at this early a stage, let alone do anything useful, let alone fun. And remember most studios have one to two orders of magnitude more people, each of which is probably individually making more than the entire DF "studio", not counting perks like coffee or health insurance.