Currently I’ve got bp-groupblog setup to create a blog whenever a group is created. I was looking for an action to hook when a blog is deleted, but was unable to find any that were called before the groupmeta for the group is deleted. I found groups_delete_group and groups_group_deleted, both of which are called to late.
I could just add a new action, but I’m trying to keep buddypress modification free if possible.
The whole group delete process is started by hooking the ‘wp’ action at priority 4. I created a function at priority 3 to save the information from the groupmeta into a global variable and use that later on. Nasty, but effective.