API changes, most recent first:
+2010-04-01 - r22806 - lavf 52.61.0 - metadata API
+ Add a flag for av_metadata_set2() to disable overwriting of
+ existing tags.
+
+2010-04-01 - r22753 - lavc 52.66.0
+ Add avcodec_get_edge_width()
+
+2010-03-31 - r22750 - lavc 52.65.0
+ Add avcodec_copy_context().
+
+2010-03-31 - r22748 - lavf 52.60.0 - av_match_ext()
+ Make av_match_ext() public.
+
+2010-03-31 - r22736 - lavu 50.14.0 - AVMediaType
+ Move AVMediaType enum from libavcodec to libavutil.
+
+2010-03-31 - r22735 - lavc 52.64.0 - AVMediaType
+ Define AVMediaType enum, and use it instead of enum CodecType, which
+ is deprecated and will be dropped at the next major bump.
+
2010-03-25 - r22684 - lavu 50.13.0 - av_strerror()
Implement av_strerror().