Dear Mobilereaders,
A great move from Amazon,

sadly I don't think I could read a book using my iPhone. (Once you try e-ink you can't go back to LCD)
But if you are so inclined you can bypass geolocation restrictions:
1- Buy a US redemption code (gift card)(eBay...)
Now maybe some fellow members could buy gift cards (it would always be more secure than eBay)
2-Make sure you're signed out of your non-US account
3- Scroll to the bottom of the page and select United States from the My Store pulldown.
4- Once the US store has loaded, click Redeem in the menu at the top right below the banner.
5- Paste the code in and click Redeem. You'll get a sign-in request, but click Create Account instead. Use a US address.
6- You'll have to agree to the iTS T&Cs first, then you'll be presented with a payment method screen. However, this time you'll see 'None' as a payment method. Leave that selected
7- Enjoy US content
This worked for me a while ago. Not sure if it still does.
Please report your experience.