Agreed, although if it's a problem limited to a small number of users, you might let it wait a couple of days. For a rare piece of hardware or an application that applies to a narrow field or specialty, it might take a while to get an answer, so perhaps bump the thread when it falls off of a slow moving first or second page (where threads might be days or weeks old).
The main thing to remember is that people want to help, and will if they can, so "machine gun" bumping, cross-posting, and duplicating threads probably won't get you an answer any quicker, and mean someone else might not get the help they need. Those actions are approximately the equivalent of cutting in line at an amusement park or movie theater, and show a disregard for others. When you're asking for help from others, it's bad form.