Since this is pretty much uncharted territory here, this whole "made-especially-for-the-internet" thing, I'm thinking that there would be a whole lot of Stuff (legal) that would be required to get this thing broadcast.
Joss said that this thing cost somewhere in the "low six figures" to do. People have bills to pay, mouths to feed, etc. so you know that everyone didn't work entirely for free.
I think once something gets broadcast, which means the studios start making advertising dollars off of it, then we get into a whole 'nother realm.
The realm of Stuff.
Yes, Joss's fans crashed the servers. But what broadcast network is going to gamble on trying to get advertisers for this thing? Because, if you don't know it, know this: TV programming is merely placeholders for advertising. If the program happens to actually be good, then that's a bonus.
And then there's the whole "penis" thing.
There are people who actually consider that word, which is the proper word for a part of the male anatomy, as a "dirty" word. (Imagine, if you will, if Captain Hammer had used the "c" word instead?)
No, I really don't see ABC, NBC, CBS…or FOX willing to have a character use that word. Especially before 9pm. They'd have Joss re-write it. Which would be bad.
I think this entity belongs on the Internet…and on DVD.
It's too precious a jewel to try to cram into the narrow confines of broadcast TV.
Plus, think about it: Wouldn't you just hate to see it broken up by commercials?
I know I would.