Why/how are some organic results on the Goolge SERPs displayed with bullet-pointed lists?

[IDWholesaler]

This post is deleted!

[seoug_2005]

Google started rolling out snippet improvements for pages that contain list. Results for these pages will now reflect the structure of the page, rather than just showing two lines of text.

If a search result consists mostly of a structured list, like a table or series of bullets, Google will  show a list of three relevant rows or items underneath the result in a bulleted format. The snippet will also show an approximate count of the total number of rows or items on the page.

[Everett]

Hello Jennifer,

I'm sorry I'm so late to the party here but I wanted to point you to a post Dr. Pete did in September:
http://www.seomoz.org/blog/how-do-i-get-googles-bulleted-snippets

Based on what I'm seeing in my vertical (namely coupons). think what it boils down to is organization. There is no "official" way to get these types of listings, but the more organized / structured you can make the data the better. That's why it's so easy for bulleted lists and full tables to get them because the delineation between the coupons is very obvious to bots.

I have also not noticed any relation to these listings and structured data markup as described on Schema.org.