This may not be exactly what you are after, but if this is something like what you want:
http://kentuckyclassroom.org/all-blogs/
Then see my reply in this thread about increasing get_last_updated from 40 to something larger:
http://mu.wordpress.org/forums/topic.php?id=6662&page&replies=3
Then download the file in the zip below, unzip it, open allblogs.php and change any of the wording you want to appear on the page, and upload it to your theme...this will serve as a new page template based on the default Kubrick theme.
http://kentuckyclassroom.org/allblogs.zip
Then log into your site, go to write a new page, and on the right side, select Allblogs as the page template and publish.
Note that there is no pagination, so if you have 1,000 blogs and you set get_last_updated to 1000 or more, then they will all show.
Steve