Here's a list of my gripes:

The N900, when in portrait mode, is upside down.

And dust gets into the speaker hole too easily.

Errrrrm............

Errrrrm............

Oh and the kickstand is in the wrong place, cos when you tap the top right of the screen the phone rocks back rather worryingly.
It's pretty scary when you're perched high up on a 4 inch wide ledge in the Andes.