SP2010 daysandnight.master does not have top navigation. to make it work simply add the following element just before the Ribbon Div.
<div class="s4-lp s4-toplinks"> <asp:ContentPlaceHolder id="PlaceHolderTopNavBar" runat="server"> <asp:ContentPlaceHolder id="PlaceHolderHorizontalNav" runat="server"> <SharePoint:AspMenu ID="TopNavigationMenuV4" Runat="server" EnableViewState="false" DataSourceID="topSiteMap" AccessKey="<%$Resources:wss,navigation_accesskey%>" UseSimpleRendering="true" UseSeparateCss="false" Orientation="Horizontal" StaticDisplayLevels="2" MaximumDynamicDisplayLevels="1" SkipLinkText="" CssClass="s4-tn"/> <SharePoint:DelegateControl runat="server" ControlId="TopNavigationDataSource" Id="topNavigationDelegate"> <Template_Controls> <asp:SiteMapDataSource ShowStartingNode="False" SiteMapProvider="SPNavigationProvider" id="topSiteMap" runat="server" StartingNodeUrl="sid:1002"/> </Template_Controls> </SharePoint:DelegateControl> </asp:ContentPlaceHolder> </asp:ContentPlaceHolder> </div>
Make sure you remove the PlaceHolderTopNavBar and PlaceHolderHorizontalNav from invisible PlaceHolder from the bottom of the master page.