Well, enotif code isn't mature yet. It does send queries to master it shouldn't send, it uses some strange integers for timestamps it shouldn't use, it handles anonymous users where it shouldn't and moreover, all database code does not check if this functionality is enabled or not. Moreover, it uses 0 as a timestamp value, does not use any timestamp abstraction when talking to database or for values. At least my devel wiki is broken ;-) Probably I'll be able to fix some parts here and there, but I would really ask for code review and fixes before making it live anywhere.
And last but not the least. For all that code it does not check if all that email notification stuff is turned on and off. Please give possibility to turn on experimental features. Cheers :)
Domas