The default pull request merge message should be the title of the pull request + the pull request id (BB-5142)
The current default commit message for pull requests just references the pull request id/ and contains no information about what has been pulled.
The pull request title usually contains information about what is being pulled in, if the default merge message used the pull request title and still referenced the pull request id it would be very useful. We are either currently copying the title in manually when accepting a pull request or developers have to look up a pull request using the id in the git log message.
This suggestion becomes powerful when combined with the JIRA DVCS connector and the upcoming smart commits feature. The pull requester places the JIRA key (Something we are already doing) into the pull request title along with the smart commit e.g. #closes . When the pull request is accepted and the pull request title is placed in the merge message, the DVCS connector will link the JIRA issue and transition it according to the smart commit.