Bullet points are great for when describing a list where items don't have any specific order of importance, but as a whole are important enough for the reader to notice. Like spacing, they make content easier to scan and remember. They also force you to keep your content concise., since long bullet points look very bad.

Bullet points provide visual distinction. It's like you saying, "I have four key points I need you to notice, so, rather than dumping them into one paragraph, I'll list them out nicely so you can easily parse them." Good, right?

There's a limit, though. If each point is too long (more than a few lines), or you have too many points, you'll end up making reading harder. In such cases, I prefer to switch to full-blown sub-sections with headings for each point.

Related reading:

• The best part about this article (PDF) is how it uses bullet points itself.
• Google's technical writing docs give some advice on using lists and tables