Pinterest - what do you think?

I just signed up for @Pinterest and trying to figure out how to use it. I haven't pinned many photos yet, but you can see the start of my boards at http://pinterest.com/IceCreamFoodFan

So far I've been impressed by the pretty pictures other people have pinned.

But I haven't been impressed with the Website or iPhone App user interface itself. Maybe I haven't figured out how to optimally use it yet, but this what I've noticed so far:

• The Website and iPhone App both are very slow to load each page, board, picture, whatever.
• The Website picture upload page is cumbersome to manually upload individual pictures using file paths. Would be great if I could just drag and drop photo files into Pinterest.
• The iPhone picture upload app insists on cropping on my photos into square-ish pics, so it keeps cutting off important parts of photos. The one nice thing though about the iPhone app is the easy to adjust brightness/contrast photo settings.
• I've tried to automatically and manually publish my pinned photos to Facebook, but this isn't working.

Basically my first impression is this could be a cool site/app, but so far a pain in the butt to use. If you have any suggestions on how to become a Pinterest superuser, please share!  Thanks