I experimented a little and found that when I take out the EditorWysiwygModeCss property setting in the following editor definition, the bullet problem goes away. Any idea what could have been causing it?
<ce:Editor ID="ContentEditor" runat="server" Width="100%" Height="600px" AutoConfigure="Simple"
EditorBodyClass="MyCuteEditorBody" EditorWysiwygModeCss="~/StyleSheets/DefaultStyleSheet.css"
ThemeType="Office2007" ContextMenuMode="Simple" EnableObjectResizing="False">
</ce:Editor>