I just used the same password to login to my Talk account in Pidgin and later for my Android. This is really insecure, especially when Pidgin saves passwords in plain text.
If you use the same generated password for every application, then you're not in that much better a situation than you would be otherwise. If you use different identifiers for each application, you can identify exactly where a breach happened from by last login time, and disable that password entirely.
It'd make me a lot more comfortable if I could lock each password down to a specific Google service (for instance: generate an OTP for Pidgin, and enable it only for Google Talk), they were a lot longer, and had special chars + numbers in them.
The point about permitting a password to be used for only certain services is absolutely a valid one, though.
Edit: To add to my reply, I have never used the remember password for Pidgin in the past, however enabling 2 step auth require me to do that. It'd be great if Google could somehow allow only the first associated app with a password for subsequent uses. Technically that looks very challenging (if at all possible).