A merge will provide you with a single commit-message, rebasing will provide you a commit-message for every commit, making it easier to remember what the intent of a change was. Sometimes that isn't clear.

Regarding the "rebase, commits will jump between features" part: that really depends on how you do things. On my projects, we use git flow. In such a scheme, every branch you would rebase, belongs to the same feature or bugfix.