From the Kdenlive Release Notes page: 

Kdenlive 0.7.7 was released on the 17th of february 2010.

This release fixes a lot of bugs reported against Kdenlive 0.7.6, including timeline corruption and various crashes. We also fixed a compatibility issue with Qt 4.6. We hope that this new release will make the video editing experience easier and more comfortable for everyone!

Kdenlive requires the latest release of the MLT video framework (0.5.0)

Some of the new features

• User selectable color schemes
  
• Improved keyboard navigation
• Timeline editing mode (normal, overwrite)
• Fix compatibility issue with Qt 4.6
• Allow shutdown after render when using Gnome Session manager
• Improved titler (now supports font outline)
• Editing properties for several clips at once (for example aspect ratio)

A complete list of the fixed issues can be found on our bugtracker.