In the all the belove nine test cases an UL (with fixed width) has three LI with list-style-type:none, 0 margins and paddings, and a 1px border (red, green, blue).
Sometimes in IE/Win the LI seem to have a minimum height.
In IE7 (and probably lower) this occurs in all the above test cases. The minimum height is equal to one line height: it varies with font size (cases 7, 9); and with line-height (case 10, but not with empty content, case 8).
In IE8b1 the LI minimum height shows up only when the LI have non in-flow content (cases 4, 5, 9, 10).
The following eight test cases 2a–10a are like the above 2–10, but now the LI have display: block. There is no more LI minimum height in IE8b1. No changes in IE7-.
Other test cases of similar problems IE8b1: list items vertical spacing problems, IE8b1: extra space with LI containing floats.