Not sure how 1Password implements this (if it's the same "pop up and confirm" process like password or not) but wouldn't Keychain's secure notes provide similar functionality? Thats basically how I track my serials and account info at home, using secure notes that must be unlocked using your keychain password in order to view the sensitive content. If keychain is syncing your full keychain contents then it seems like this will be included.
1Password allows you to enter more meta-data like purchase date, purchase price, purchase location (store), has fields for support email, support contact name, etc.
So when you want to price compare from last years version, or need support, you have your serial number, order number, email or phone number to create the request all from one screen.
Sure you can type it in notes, but 1Password does a great job of storing this info. Plus you can create tags for quick searching when you have a lot of serialized software titles.
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I am a long-time 1Password user. I was one of the people who complained, loudly, when 1Password removed LAN-based syncing in favor of either iTunes or cloud-only options. (To AgileBits' credit, they now have a beta USB syncing utility which somewhat addresses the problem.)
It amuses me to see people suddenly concerned about cloud services, now that the PRISM news rubs everyone's face in it.
I'm sure iCloud Keychain will be very nice for those who use Safari only and don't care about the cloud. In the meantime I will keep my passwords file--encrypted or not--off cloud services.
I'm not opposed to cloud services for documents, but keeping all your passwords on third-party servers is just asking for trouble.
(Yes, a properly-AES256-encrypted file is unlikely to be decrypted--if the encryption has no bugs and there aren't any surprise escrow keys. Very recently Apple had a bug where FileVault was logging plaintext passwords to the bloody system console. The impact of that bug is much less severe when there aren't a zillion copies of your encrypted data everywhere.)
This is why I hate that 1Password won't use WebDAV and only Dropbox or iCloud. I rather be the 'owner' of my data.
I have two Mac Mini's, one at my place and one at my parents, both behind a firewall. Both Mini's run OS X Server with a VPN connection to each other. Data is sync'd across regularly and encrypted. I can connect my iPhone and iPad over VPN to either server to get my data. This method provides me with an off-site location, ownership, data replication, and security. The fact they live 1,200 miles away also helps that if my server is down due to hardware or local network conditions, I can still connect to another region of the US where it may not be impacted. Or if I happen to visit them, I'm pulling data locally or from a closer 'server'.
Most apps let me sync my pref's or files using WebDav, except for 1Password. This is the one reason why I may actually ditch the app!
I wish I could setup another Mac mini on the west coast, as this would give me three geographic points to connect and replicate too.