Multi-track format allows interleaving of video and sound
Auto-save and undo support
Audio files, in multi-track, can be cut to tight synchronisation with your video
A wide range of effects and transitions are included and can be customized
Wide range of supported codecs for both input and output: DV (PAL/NTSC), MPEG2 (PAL/NTSC/HDV), Flash FLV, WMV, AVCHD (HDV), H.264, H.265, WebM (VP8, VP9), lossless ProRes, MP3, AC3, OGG Vorbis, FLAC and more
Can be seamlessly used with compositing editors such as natron or blender. Natron is a GPLv2 compositing editor for special effects in a similar vein as after effects and is an excellent sister project for kdenlive.