The default Unity menus continue to be displayed on mouseover, but with this change, there's now an option available via Dconf Editor (com > canonical > unity and enabling "always show menus") which allows setting the menus to always be visible. This feature works with both LIM (locally integrated menus) and global menu (AppMenu).
The "always show menus" option was added for Ubuntu 14.04 LTS with Unity version "7.2.4+14.04.20150316-0ubuntu1", which is currently available for the brave in the Proposed repository, and once it's properly tested (probably a few days), it should be promoted to Main as an update for all Ubuntu 14.04 LTS users.
You can see the always show menus feature in action in THIS video I recorded a while back under Ubuntu 15.04 Vivid Vervet.
Along with this feature, this Unity version also brings various other changes, like enabling Dash, Hud and the session dialogs over full screen windows, along with bug fixes. A complete changelog can be found HERE.
Update: this Unity version is now in the main (stable) Ubuntu 14.04 LTS repository.