Just a possibility. If you have more than one language installed in your farm, you need to take into consideration the title resource property:
SPList list = web.Lists.TryGetList("Announcements");
if (list != null)
// Create a navigation node pointing to the Announcements list.
SPNavigationNode newNode = new SPNavigationNode(list.Title, list.DefaultViewUrl);
// Add the node to the Quick Launch area.
SPNavigationNodeCollection quickLaunch = web.Navigation.QuickLaunch;
// Copy translations of the list's title to the user resource for the node's title.
foreach (CultureInfo culture in web.SupportedUICultures)
localizedTitle = list.TitleResource.GetValueForUICulture(culture);
In your case, if your current culture is en-US, just try to check the following to see if this is the issue:
foreach (SPNavigationNode node in web.Navigation.QuickLaunch)
if (node.Title == "Parent Title")
SPNavigationNode newNode = new SPNavigationNode("Title I want", myList.DefaultViewUrl);
newNode.TitleResource.SetValueForUICulture("en-US","Title I want");