Tickets all the way. I haven't seen forums that enable you to manage and monitor support requests the way support ticket suites do. They feel like organized chaos, because they are. And stuff gets lost. And overlooked.

If you've ever dumped your support question in a forum and never gotten a response, that's no fun. With a ticket, there's a higher level of accountability. Too many times things get lost in forums, at least in my experience.

It depends on the price point of the product and degree of difficulty of the product as well though. I associate higher dollar products with support tickets and lower price point products with forum or FAQ support. Let's be real here, FAQ's can be helpful, but I don't think they constitute customer support.

Forums are great because users can help each other, which might be fine if you purchased a $20 piece of software, but not ok when you're running into issues with a $1000 dedicated server.

Short of phone support, I believe tickets are the most comprehensive way to give your customers the fastest and best service possible. :) Support tickets also provide a more organized means of not only reviewing tickets for quality control but documenting issues over time and then returning to past issues if needed.