I have two SSO accounts. Can I merge them?
Yes, but SSO accounts must be merged manually. This will allow you to log in using the email address(es) for both accounts. However, note that you will lose access to every site attached to one of the accounts, so choose carefully which account you would like to keep.
Choosing a primary account: To see which sites are attached to each account, log in to your SSO accounts one at a time at https://login.ubuntu.com/ . It should show a list of other sites you have recently logged into via that account. This list represents the sites that you will lose access to, on whichever account you merge from. The account you merge to will remain intact, though.
Merging other accounts: Before merging your SSO accounts, you should take care of any openID consumer sites or services you may have accounts on. For example, if you have two Launchpad accounts, you should manually merge those first. If you have two Ubuntu One accounts, you will need to back up the files from one account and copy them to the other account. Then you should be ready to merge your SSO accounts.
Sending a request: To request a merge, send email to ISD from the address used for one of your SSO accounts, with a subject line like "merge SSO accounts - My Name". Please specify the email addresses of both accounts in your message, along with acknowledgement that you don't mind losing access to everything attached to the non-primary account. Be clear about which account you want to keep, since you will lose access to the sites associated with the other account(s).
After sending a message, you should get an automated reply. Please respond to this automated reply using the email address of your other SSO account, to confirm you have access to both addresses.