Can you draw the tree with the circles vertically staggered instead of directly adjacent, so the circles are vertically ordered by time?

http://3.bp.blogspot.com/_aHXMSfhY_hY/TFxP-Eoc3rI/AAAAAAAAAH... is an example of similar data.

You could have multiple panes/columns of data, one for the graphical tree, one for the date for each node, one for the username for each node, and one for a node comment.