known or used by others in this country, or was patented or described in a printed publication in this or a foreign country
Now to me it seems that a blog post can be classified in this day and age as the modern equivalent of a "printed publication".
So here is a simple idea, any time you have an idea, just quickly right a blog post on it. Then in later years you will never think "but I thought of that" when you see a patent application that is just an obvious thing with paperwork. Most of the dumb ideas are things that people either implemented, or thought about, and just didn't bother getting them patented because that would be silly, and didn't even publish the information because it was so obvious.
If every idea that is had is blogged about then rapidly all of the obvious ideas will have clear and documented prior art. You think its obvious that you could use a PVR to create targeted ads? Blog about it, use the technorati tag "prior art" and suddenly there is prior art to cite. By publishing it like this you are clearly saying "I'm not going to patent this idea" and you aren't going to get into some silly license argument. The reason to publish your ideas is because you don't like the current patent regime and you want to get rid of silly patents.
Now clearly I'm not a lawyer, but under the definition of the US Patent Office why wouldn't that count?