Adding information to Activity e-mail notifications ??

Having recently upgraded to 1.5.3 from a lower version, I'm a little disappointed in the e-mail notifications lacking in content now. My question is, where can I add and what would I need to add to give more information to the notifications? I would like it to tell who made the change and their IP address. Of course the timestamp on the e-mail header is obviously a good time to go by but it would be nice to include a timestamp in the notification as well.

I know 1.4 used to include some extra information - wish 1.5 did as well.