The problem with password managers (or any scheme that creates unique, non-memorable passwords) is that should you need to access a particular service when you don't have your manager available, you're SOL. Being able to pull things out of dropbox and whatever on your phone are nice, but it's another thing to have to rely on.
I've thought a bit about this in the past, mostly relating to setting remote shhd to disable passwords entirely, and only accept PKI logins - what if you need to get in, and don't have your key?
The google 2-factor with optional 'emergency 1-time use codes' that you can print and carry in your wallet is a nice solution to half of the problem (the other half being, if you're not using a computer you control, how do you securely access your password manager?)
I don't really have a solution, other than "remember to take your phone with you", and possibly "ensure that at least your primary email is accessible via 1-time codes or a memorable (and strong) password."