iPhone Fingerprint sensor for passwords Is there any way I could setup the fingerprint I'd to work in place of typing in my iCloud password whenever prompted, or perhaps even other passwords in keychain?

I had to upgrade to a 5s yesterday and as is the fingerprint id thing seems pretty useless if I can't set it up as a replacement for passwords.
If your device is jailbroken, you can install iTouchSecure which lets you use the Touch ID feature for any password entry area in any app, including iCloud password dialogs.