I agree that some of the issues discussed in BMCDN should go to Customer Support, especially when they are related to a bug, but in many cases this is still a good place to start. I have seen posts in BMCDN where it was determined that the person with the original post should contact Customer Support because the issue couldn't be resolved here. A good guideline may be to contact Customer Support when your issue can't be resolved within a couple of days
I have found that most of the time I can find an an answer faster, in hours rather than days, by using BMCDN. Also, I sometimes find more helpful answers here than in their knowledgebase. In some cases I have even been sent here by Customer Support to get an answer to my problem. Since Customer Support uses this as a resource, I would hope that those responsible for BMC products would monitor BMCDN to gain an awareness of what problems we are having and take actions to make inprovements to their products.