Previously, I believed chaning menu title is in Menus->Menu Manager and edit the menu -> title. That is only for display at administration side. To change the display name in front page, you go to Extensions-> Module Manager. Each menu is related to a module, for example, there is a Main Menu module. So, you need to edit the module for changing the title.
Not long ago, a security release of WordPress has been pushed to the user. There are a new one today at http://wordpress.org/development/2009/08/2-8-4-security-release/.
WordPress 2.8.3 is released. They said this is a security release for 2.8.1. So, I think everyone should download that.
Please download at
Moreover, I read an article at WordPress.org. 2.9 will come very soon.