1. When I go to the login page on my PC or Nexus 7, I see a blinking caret at the beginning of the "Email address" text and I have no idea whether I need to select that text so my typing will overwrite it, or if I should just start typing.
2. When I go to the page on my Android phone, I don't see the "Email address" text at all, just a blank field with no indication of what goes there. I have to tap outside any field to see what that field is for.
I don't think labels inside fields should ever be combined with automatically putting the focus in one of the fields. That forces you to leave the label in place when the focus is on a field, which is a recipe for confusion. Conventional labels are much more friendly.
After I type in my email address (in the .to domain; see my profile here), it shows me a picture of myself as soon as I complete the address. That's cool, but when I hit Tab to go to the next field it says "Did you mean mg@me.com". Huh? Perhaps if you find that you've succeeded in fetching a gravatar, you should not use the "did you mean" message. The gravatar itself is a better confirmation that I've got the right email than any possible second-guessing you could do about domain names.
Also, your blog is pretty hard to read. The text is barely more than 50% contrast, really faint and washed out. Why do modern web designers think text contrast is their enemy?