I'm not sure this is an ordinary use case, but I often have the same password for different sites. This could be two google accounts with same password, the same password for amazon.com and amazon.co.uk and even more when developing where I could have the same accounts for production and developing. Also nice feature for sites sharing login information or sites with different urls for different things.
Could it be possible to link these accounts so an update to either account will result in 1Password asking me if I wan't all accounts updated or only the current account updated (and the link between the account broken).
Hope you can fit this in a some point! And thank you for a very nice product.