A big thanks to @grundleborg, who recently contributed a pull request that added a shortcut for quickly linking to channels. You can come sign up for our daily builds site to try it out.
This feature is similar to the #channel used in IRC, but in Mattermost # is used for for Twitter Style hashtags. Currently the feature is implemented using an exclamation mark !, but we wanted to have a last discussion to finalize what symbol should be used.
After this feature is released, the symbol won't be changed, so if anyone has thoughts or comments please comment here soon!