We were running into issues with how CiviCRM activities are showing in Drupal Calendar (Views). Drupal is adjusting the provided activity date/time based on the user configured time zone. For us, this is desired behavior because we have users crossing multiple time zones who want to see the time the activity is executed in whatever time zone they are in.
After a little research (and finding these threads:
https://forum.civicrm.org/index.php/topic,23411.msg98329.html#msg98329, What timezones should we use on the server and database?, though there are many more tangentially related ones) it appears that CiviCRM assumes that all users will be in the same timezone and stores activity date/times as the local time into the database. Drupal expects that the stored times are in UTC, hence our issue. Would a "simple" fix of converting the activity datetime column format to a timestamp format in mysql be a reasonable fix? I'm worried that we're going to run into this in multiple places...
As an aside, I think it would make sense as a future change for CiviCRM to respect the Drupal user configurable time zones.