If you write about things other people write about it's not impossible for Panda to get confused and think you copied it (identical) or plagiarized it (very similar).
The tragedy is this can happen to the writer who didn't look at other sites' pages and the writer who did.
It is more likely to happen when:
a) the page is short;
b) the subject matter lacks details;
c) the writing style is very basic; and/or,
d) somebody else wrote about the subject before you did.
Some sites still Pandalized have already made changes related to a) and b); it may be worth looking at c) and d).
Topics already covered or even beaten to death aren't of much interest to Google. Panda hates copied text and perhaps also copied topics.
I know very little about anything so my future on the web doesn't look great right now. I have no idea how I'm going to come up with lots of unique content and original analysis written in a distinct style.
Vince and Panda are each huge burdens but together can virtually put you in the gulag camp. You can do tons of work with very little if anything to show for it. For me Vince and Panda created a huge chilling effect on starting new projects.
A year ago everything looked so different. Then the web looked like my future; now it looks like my past. I used to have the confidence that if I did good, hard work, I'd get results. That confidence has eroded each month since Panda was introduced.