that is to say, instead of each teaser being treated as a distinct div, with the bottom of the image delineating its own region, the text from the next teaser will flow up into the previous one if the text is smaller than the image.
The img align="right" makes the image float. All of the following elements will flow around it. You can use the css clear property (http://www.w3schools.com/css/pr_class_clear.asp) in one of the following blocks so that it has "clear" margins to fix this. Playing around in firebug, the following css would create the layout I think you want:
.main-content .node .links { clear:both; }.
The selector is on line 357 of style.css. and is tied in with .main-content .node .terms. I'm pretty sure can simply add the text about into the style sheet, but you may have to split the two selectors apart.