If I remember correctly even Steve Gibson, who sang praises of the Apple security apparatus saw the iCloud as a weak link in iOS security in his three part series (sn 446 through 448) on TWiT.
I think products like 1Password, Keypass, Lastpass, etc. are a good idea, in that they're making it much easier to encourage a culture of strong, unique passwords for every application and website. Of those, I favor 1Password, because the people making it have a good track record of making generally good security implementations, and being receptive of feedback when issues are discovered. They've been good about updating the apps when an issue is discovered, and haven't made it a super regular occurrence.
They also allow flexibility of storing the password database, which I prefer over the services that store your passwords with them, as you are now reliant on their own security implementations. If you want to, you can store it in dropbox, so that you can access the web-based version anywhere you can log into the Dropbox website. You're now putting an awful lot of faith in the security of Dropbox, but it's an option at least.
But fundamentally, this is a problem which should be solved by the ecosystem providers. Windows, Mac OS X, Firefox syncing, Chrome (I assume Chrome has a way to sync passwords to wherever you're logged into, I don't use Chrome).
I'm comfortable enough trusting Apple to secure all my login credentials that I'm willing to use the built-in functionality. Much like how I use "Reading List" instead of any of the "article saver applications". It works fairly well, I don't have to mess with it, I don't have to give my data to some other company, it just shows up in all my browsers on all of my devices.
It can autofill credit card numbers and passwords on my iPhone/iPad.