Personally I've waited 1 to 3 days. All minor problems though. So it probably depends on the complexity of the issue.
For me usually just depends on the time of day I submit a ticket. If GM asleep then it takes a bit longer, if they're awake its not very often I wait more than a day for a response. Sometimes the responses can be pretty poor hinting at a lack of understanding about what has been asked in terms of something to do with gameplay. Support for technical issues however is generally much better than general gameplay enquiries.