I believe since patch X there are some messages missing in the replays such as:
- some system messages (eg kick/ban votes)
- messages sent by admins (/msg)
- custom RCM messages (sent by admins or insim apps)

I have replays from patch U+ where I can see all of the above messages.
We can now hear the sounds of some of the messages but they are not shown at all.

These messages are quite usefull in some cases (for admins and for league races) and I'd wish to be able to see them all.