Google's Openid login support has been discontinued. Many Branchable users relied on it to log into your sites, and you'll find that once your existing login cookie expires, you can't log back in via Google.
We recommend getting an openid from a different provider, such as http://pip.verisignlabs.com/. If you created a Branchable site using a Google openid, you should email us with your new openid, so we can update your site to use it.
Update: Seems that Google has changed their minds and their openid is going to continue to work until April 2015 or possibly 2017. We still recommend changing to a different openid provider.
Update: Discontinued for real as of 23 April 2015. See login using email address for a new way to log in.