I'm a long time if infrequent user of support forums, and one issue I have encountered with popular support forums (e.g. Ubuntu Forums) specifically is the rapid bogging down of support sections with new support requests. The necessary implication (on popular support forums) is that any given support thread has an often short residency on the first or even second page of its section, and is swiftly lost in the noise of new support requests. If one is lucky, someone will chance upon your support request during the short residency time (more likely if the question is comparatively trivial?), if not (as I so frequently am) you may get a sizeable number of views in that time but no useful responses (and as time goes on, the likelihood of ever getting a response diminishes).
Of course, forum administrators will be best placed (having access to the statistics) to know precisely how much of an issue this is. However, I would guess that there are a sizeable number of abandoned and unsolved threads which have fallen victim to this. Personally, I have a week old support request that I have bumped (and I do loath bumping any thread) two times to no avail, and intent to bump it one perhaps two more times (in a week or two) but after that, I'll abandon the thread as I have so many others (not many on Ubuntu Forums granted, I'm new here).
I suggest a solution in the form of a separate sticky section of 3-5 random threads in any support section. This sticky section would be placed either below the current sticky section or at the bottom of the first page (so as not to prioritise these random threads over new threads), and would contain a random selection of support threads under the age of 30 days and marked unsolved. There could also be weighting system to slightly prioritize support threads with no/few replies over those with many replies. Also, an in-page refresh button allowing readers to generate a new set of randomized threads (negating the need to refresh the whole page) would be nice.
Another solution would be to implement a formal 'bump' option that would allow the author, or perhaps any reader, to bump a forgotten thread. This feature would negate the need to actually reply "bump" and could perhaps place restriction on how frequently, and how many times a thread can be bumped (maybe even exclude thread over a certain age, e.g. 1 year).
Anyway, these are my humble suggestions on how to improve a popular support forum. I've used many support forums in the past, and it's rare that I find a solution for a non-trivia issue. Paradoxically, I've always gotten better hit rates on comparatively unpopular support forums (longer residency time on the first page).