I have just been though a foreclosure and the eviction that followed. The process service included an incorrect time to appear in court. Both myself (defendant) and the Attorney for plaintiff were not at the court scheduled time. The Judge dismiss...
Without knowing more specifics about your jurisdiction and the case, dismissals without prejudice are indeed dismissals and conclude the matter. Your case is no longer a case, and does not exist. The significance of being dismissed "without prejudice" means that the matter can be refiled, but that until that happens, at which point a new cause number is typicall assigned (depending on jurisdiction), you are no longer a defendant in litigation. Dismissals without prejudice are rarely significant except in situations where statutes of limitations or other such procedural hurdles are implicated. Even so, you can expect all sorts of arguments for tolling the statute or the like on behalf of plaintiff's counsel to try to save the action.
If the Judge didn't amend the order immediately, or hear the matter on short notice once all parties were present, you can assume that the dismissal will stand. The docket appears to have confirmed that for you. Without a motion from the plaintiff the Judge is not likely going to set aside his order and reopen this case, although I've seen some very strange things from the bench in my years of practice.See question