Notifications is the only thing I hate (well, almost hate) in wp8
Ok, I'll just write a list of things that make me mad and you tell me if I'm being picky or had it all wrong, or I am right and MSFT has a lot of work ahead considering notifications:
1) Centralized notifications in Me hub are pretty cool, but why can't I put'em up on the lockscreen? And why there's no toast option for them? Mail app - same here, why y no toast?
2) Both Facebook and Skype notifications seem to run as random as possible. Sometimes I don't receive notifications, sometimes I do. Sometimes they are being marked as read, when I open up app, sometimes they don't. That is really sad comparing to IOS notifications, that are really fast and synchronized with the service.
3) Messaging notifications. Both Skype and Messages app (facebook chat) don't seem to care wether I use them or other client for messaging. I may start to chat on the phone and then continue on my PC, and I don't understand why Messages or Skype can't keep up and shut the notifications down in that case like GTalk does (only 1 active client should receive notifications)
4) Ok, notification center and push-server is a must, I can see that now after a week using wp8. I still love the the os though, just wish MSFT put some extra work here to get things right.