There was a nice article series on boingboing a few weeks ago written by a manager of SyFy explaining why they do those things you mentioned.
[edit]http://www.boingboing.net/2010/05/13/explaining-12-things.html#more
there are more, just google[/edit]
I remember they already confirmed a second season for Caprica no matter what the viewing ratings are.

Btw, i'm a bit disappointed by sgu, but thats a whole different story.