The English Wikipedia has raised some concerns (permalink) about the new edit summary lengths (T6714). There are some cases where the full edit summary length was accidentally used, and this is cluttering the revision history (example). Additionally, there are worries it could be intentionally misused, possibly as a venue for discussion during edit wars, for instance.
A possible solution is to truncate the display only within the interface, and not the storage (props to @Legoktm for the idea!). A clickable/hoverable ellipsis "..." or something similar would reveal the full summary. This way everybody wins -- we can take full advantage of the longer edit summaries, and abuse and visual distraction will be minimized.