I'm in 1.5 and the code is slightly different. I want it to show ALL dates, past and present.
I just took out the reference to the date in templates-functions-category.php:
WHERE post_status = 'publish'
AND post_date_gmt < '$now' $exclusions
becomes
WHERE post_status = 'publish'
I don't know if I need "$exclusions".
To get the Archives to count future dates, I changed the following in template-functions-general:
if ('monthly' == $type) {
$arcresults = $wpdb->get_results("SELECT DISTINCT YEAR(post_date) AS year, MONTH(post_date) AS month, count(ID) as posts FROM $wpdb->posts WHERE post_date > '$now' AND post_status = 'publish' GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date DESC" . $limit);
To:
if ('monthly' == $type) {
$arcresults = $wpdb->get_results("SELECT DISTINCT YEAR(post_date) AS year, MONTH(post_date) AS month, count(ID) as posts FROM $wpdb->posts WHERE post_status = 'publish' GROUP BY YEAR(post_date), MONTH(post_date) ORDER BY post_date DESC" . $limit);