FeedDemon's news bins enable you to store news items in a central location, providing a handy way to collect items from different feeds. If you find an interesting item that you might want to read again, just store it in a news bin for future reference.
A news bin is useful whenever you want to store items. If you're a researcher, you could use a news bin to hold items that may help in your research. If you're a blogger, you may use a news bin to keep track of items you'll blog about in the future.
A watch automatically collects items containing specific keywords, whereas a news bin provides a way to manually collect items. Since the contents are defined entirely by you, you have complete control over what goes into a news bin.