Bug in YahooGroups
If you are subscribed to more than twenty to thirty yahoogroups and when you view them online by default it shows up in 'Expanded Mode'. When you select 'Edit Groups' and do changes like the 'delivery email' or the 'delivery frequency' for the first page displayed, it again reverts back to the Simple mode. Now you are in a batch edit mode, you would need to select '2' to locate page 2 and then again choose 'Edit Groups' tab. When I closely viewed what is happening, they are just missing out a querystring argument edit=1 between the server roundtrips.
http://groups.yahoo.com/mygroups?o=2&page=2&edit=1 would open page 2 in edit mode. When you submit 'Page 2', you would see that 'edit=1' no longer appears. I believe Yahoo should come up with a Batch Update mode to address this usability issue.