Network and Cable must be scrambling to figure out how to make money...
Not cable, they're growing. Network TV is more vulnerable since they have no subscription revenue to offset declining viewership.
In theory, the downloading market will grow to compensate for the losses elsewhere, but those numbers are still very trivial compared with old fashioned ad revenues.
As for Netflix, it'll contribute to revenues indirectly, like DVD rentals and sales as a whole already do.