I used public forum when I had an issue with shares. After that I posted details in PM, shares were recalculated and the issue was fixed (not for me only - for the EU server users, it was an accident case when stitching data from worldwide servers with Ethereum).

Also when my friend had an issue with CoinMine, he created a ticket using pool site and did not receive an answer. Then I post a PM to pool operator on forum and received almost instant reply that solved the issue. I don't like that, but seems that social networks and forums sometimes provide better support than emails/tickets. Don't ask why, maybe due to public nature of those requests...