Use only the close button, get rid of the hide one. Notifications should be pushed to the notification area after the few seconds have expired and if the user has not closed them himself.
This way if you want to see something later, just don't click the close button. As it is, they are close enough that it would be easy to misclick and manual hiding means you are actively going out of your way to, well, not be distracted. And that is distracting.
Quite like the texture and how you organized it, looks pretty good.