I've been staring at the icon for a while now, but I cannot figure out what it's supposed to BE.

Messages: That's an envelope. Ideal.
Shopping Cart: That's a shopping cart. Perfect.
Notifications: That's a... Well, it's a... It's a... thing, innit?

Can anyone help me? It's driving me mad.

It's a globe, but the American version that puts the Americas at the front, rather than the more Euro-centric version we're familiar with over here. It lights up to indicate you have notificatioons from the WAM world, or at least that's how I've always taken it.

I've been staring at the grey shape, I should have been looking at the black shapes. I see it now. Thanks!

Does this help?

Or it's Ghibli's No Face looking wistfully up and to the right.