Some developers may probably read the bugtracker more often than the forum; and the bugtracker offers tools to track the progress of fixing the issue - a forum does not really. So the more serious such an issue seems (the more annoying it is, or the more people could get annoyed by it), the more one might recommend you to create a bugtracker task (after searching in all existing tasks, even closed ones, if it was not already mentioned before). I am not certain, though, what the current opinion about "flooding the bugtracker with trivial issues" is...