No features have been removed. But they have been moved around and renamed. What was previously the Windows XP style is retained as the 'Classic with two columns' style but the skin it uses by default is different depending on the OS so the Start Menu blends in with the look of the OS. After choosing 'Classic with two columns' style from the Style tab, go the Skin tab and there you can choose Windows XP Luna skin returning you to what you had in 3.6.8 as "Windows XP Style".
Similarly, what was earlier the 'Windows 7 style' in 3.6.8 is there under 'Classic with two columns' style (just set the "Windows Aero" skin) from the Skin tab. The real Windows 7 style in 3.9.x is a brand new style designed to closely imitate the real Windows 7 style menu with inline All programs and search results (yet in this style, you can have a cascading All Programs menu - such is the versatility of Classic Shell).
We will not remove features like Microsoft does. Believe us, we care about our users and removing what they developed a liking for is not something Classic Shell does.
If you want the Windows 7-like look but with the main menu animating, choose the 'Classic with two columns' style. The skin can be anything you like - XP Luna, Windows Aero or Windows 8 - which you set from the Skin tab after picking the base style. In fact, the Classic with two columns style is the most powerful of the 3 styles because it allows accommodating many items in the menu, including subitems.