@electronicmail,
For now, you can do it manually if it really drives you crazy. I'll be covering it in more depth in the next section of tutorial that I am writing. Here's a quick description of it:
Make use of the thumbs up/down system to collapse topics that are of no interest to you. Click the thumbs down on a topic once and it will no longer be in your lists, all you'll see is a line that says "Topic voted down." To view the topic again, click on the View link to expand it.
Here's a graphic that shows you what your lists with collapsed topics will look like:
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