The King Is Dead! Long Live the Queen!
After the problem that prevented me from entering the first time, I found that Paizo also has a few free items so you can find out about their setting and thus write things about stuff they already own, which is what helped me in the other one. One of the interesting things that I noticed is that the Queen of Korvosa is rumored to be sleeping with her female bodyguard. (Although it's only one sentence, at least they didn't feel the need to throw in anything claiming that's any more scandalous than any other affair, like in the one I mentioned earlier.) In any case, given the depictions of the King (it's debatable whether he was still alive at the time of the portrait) and Queen, one can hardly blame the rumormongers-or the couple, if it's true.
Of course, they're trying to run a business, so the information in the free stuff pales in comparison to the commercial products. Interestingly, they've chosen to do most of their background expansion in their adventure serials. As you can see from its pilot, the current one centers on city and the Queen. (The latter part is expanded in later issues, but those are heavy spoiler information.) In addition, I have an idea for an adventure set in Korvosa, so it may be worth buying those and/or the city guidebook to build up my knowledge for the next RPG Superstar contest.
In addition to this, Paizo is also making its own version of the RPG based on D&D v.3.5, so it will not have to be heavily updated. Sadly, they aren't allowing others to use it, so anyone else using the d20 System will have to do the same themselves to avoid having to make new rules every time the Wizards decide to replace the base. The guys who tried to make a better ruleset* (and succeeded, except that they didn't fix the most fundamental flaw enough; it's also compatible with Pathfinder) also require you to make a deal with them to use their enhancement, unlike the d20 System and OGL themselves.
*By the way, I hear that the original True20 setting includes a lot of characters who don't make pointless restrictions on whom they love based on what equipment they have. I might look into that, too.
Edit (2008.04.05): Updated here