No login form on login page when reCAPTCHA is turned on but no keys provided.
After trying to deal with the issue described in my previous question (http://askbot.org/en/question/6881/input-error-k-format-of-site-key-was-invalid-when), I decided to just turn reCAPTCHA off on my hosted site until I could figure out what was going on.
I removed my public and private keys, but I forgot to uncheck the "Enable recaptcha" checkbox:
I saved the settings as pictured above. When I went to test the login, I found that the login form no longer displays!