This simple module allows the colon punctuation mark to be removed from field labels.
Configure each field that you want to remove the colon from on the 'manage display' admin interface, click the 'gear' icon to configure the formatter and select to hide the colon. This can be configured for every field individually, and for every view mode that the field can appear in - nothing is changed by default when the module is initially turned on.
This is very similar to the No Colons project, but that does not have a Drupal 7 release and I couldn't resist using this project name! If anyone finds the name offensive, please raise an issue in the project issue queue - no offence is meant.
Unfortunately the only way to provide this functionality is to override Drupal's default field theme function. Any themes that override this, or any of its suggested theme hooks, will work with Colonectomy as they could. For example, the Bartik theme overrides the theming of taxonomy term reference fields, so those fields can end up with either one or two colons (never none) depending on the setting to hide the colon.