I would go with:
"forgot your password" -> "forgotten?". Make sure its grouped right next to the password field so its context is obvious
I would also eliminate the text labels "username" and "password" and have them defined IN the text fields (similar to some search boxes).
If you are truly looking to go minimalistic I would recommend that you incorporate the new account sign up page on the same page.
Take a look at twitter.com main page,
A wonderful example of a minimalistic and intuitive design:
(make sure you are logged out first to see their sign in / sign up page)
Finally able to post the image (Rep was too low as a new user) a good picture is worth a thousand words:
Note for the 'New to Twitter' signup is only 3 fields, no text labels, sign up instead of submit. I could go on and on :).