I see a lot of the replies to SuperSquid's post seem to dismiss the problem as simple "ratings economics."
But there is definitely a "chicken and egg" element to viewership. I.e., which comes first, the audience or the station's commitment to building an audience?
Even the best network shows crash and burn when dumped into a bad time slot or left without promotional support.
For years, one of the best shows on Speed was the World
Rally Championship. But a constantly-changing late night time slot, zero promotion and near xenophobic reluctance to cover something so spectacularly "unamerican" (the races are held virtually everywhere except North America) guaranteed poor viewership. (After a few years of religious viewership, I gave up trying to find the show in Speed's ever-changing shedule.)
Historically, there are numerous examples of viewer write-in campaings that pushed networks to do the right thing.
One of the best-known examples is Star Trek. The original TV series earned a small but devoted following. When the network pulled the plug, they were flooded with letters from fans. The show returned for another season and eventually became a huge hit, spawning movies and countless other "generations" of TV series.
The bottom line: yes, TV is all about ratings; but ratings are a function not just of show quality or viewer/advertiser support, they are also a function of network commitment and vision, which vocal viewers can and do influence.
So don't be shy, tell Speed what you want. Chicken or egg, if enough viewers are vocal, they will eventually listen.