When one runs a SQ analysis on a project, nothing clearly identifies the project in the logs - except if you look at the line ANALYSIS SUCCESSFUL, you can browse ... at the end of the logs.
Now that we are adding support for organization, the project key is going to not be enough to identify precisely the project. The sonar.organization information is highly wanted. For SonarQube.com case, having this information in the Travis CI logs would help a lot to debug some configuration issues (like you're not pointing to the right org, or there's no org with the given key).
As a user, I therefore expect to see something like this in the logs:
If no organization key is provided, I expect to not see the "Organization key" line - in order to not disturb on prem users who don't use this feature.