To be fair, they're using the same shade of blue that AT&T uses for its logos and corporate art. Go to att.com, and everything is that shade of blue. Verizon, by contrast, uses red in its logos and corporate art. They're just using the same identifying colors that each brand has already chosen.

No you can't.

There's no authentication of you besides your user name, so any attacker could just take the user name you submitted, give it to the bank, then show you the "security image". Classic Man in the Middle attack.

That's no more true for a Kindle than it is for an iPod.

If you buy DRMed books from Amazon, then those books won't be useful on other devices. But, just as there are many sources for un-DRMed music, there are many sources for un-DRMed ebooks. Use one of them.