Thanks! It's important to note though that I didn't design the theme; when I received the templates they were already in HTML and CSS files. It took some translating of classes and IDs from the designer's original files, and then a lot of work to get Drupal's output to match the HTML that the CSS expected. The theme code is divided up into a number of tpl.php files for different node types, a template.php file with quite a few theme function overrides, and a separate views_theme.inc file that handles the theming of the views used on the site, since its a relatively isolated chunk of code.

The 'listing' format I think you're referring to -- with each node shown as a two-line blurb in a month-by-month list -- is used all over the site. I created a generic theming function that accepts a view, and whenever I had a page that used a view, I tossed it into that theming function to generate a consistent look and feel. I did indeed use 'full node' views so that I'd have access to the complete node data, but I didn't have to do any additional queries beyond that.

The "separate nodes by date" bit was done with just one theme 'helper' function:

function theme_date_header($date) {
static $formatted_date;
$new_date = format_date($date, 'custom', 'F Y');
if ($new_date != $formatted_date) {
$formatted_date = $new_date;
return $formatted_date;
}
return FALSE;
}

function my_theme_function($list_of_nodes) {
foreach ($list_of_nodes as $node) {
$header = theme('date_header', $node->created);
if ($header) {
$output .= $header;
}
$output .= theme('node', $node);
}
}

Obviously, the formatting in the above example is all but nonexistant -- on the EOS site the $header is wrapped in a couple custom classes, etc. But the idea is the same. The helper function takes a date, and formats it as a string of text containing the month and year. It keeps a static version of that formatted text around, and each time it's called it compares the new incoming date to the last one it received. If they differ (IE, the node being formatted is the first one from a new month), the two formatted dates differ and it changes the 'stored' copy and returns the formatted string. In 'my_theme_function', every time I call it I look to see if it returned some text (ie, a formatted date) or FALSE. If it returned text I print out the date header. It takes a little squinting at first but it works very, very well in practice.