According to John Perkins over at NewTek:
"It is an incremental update to SE 1.5.1, so you should have the 1.5.1Just thought you all should know. You can download it from Register.newtek.com as usual.
update installed first.
It fixes several file reading problems
Fixes NTSC DVCam (Sony SD) MXFs
Fixes MXF audio problems on files over 2GB.
It fixes several MPEG reading/seeking/file length problems.
It adds support for TriCaster 2.0 projects
Adds an optimized reader for the TriCaster 2.0 I-Frame MPEG capture format."