The full list has yet to be published by the developer. However, a shorter version – featuring the main fixes – has been made public on the  Empire: Total War forum:

– Load time detection on trade routes to fix pathfinding crash in campaign (this fixes a crash to desktop)
– Some General Sound balancing improvements (this fixes some unit sound problems)
– Fixed UI Chat hang when spectator leaves unranked match with 3+ players (this fixes a multiplayer problem)
– Addressed several code issues causing crash to desktop
– Fixed several save or load issues
– Corrected campaign map agents behavior (this fixes a crash to desktop)
– Fix to animation glitch causing repetitive sounds when battle is launched.

That’s it for now. Undoubtedly, some more minor fixes will find their way within the update as well. Until then, keep your armies in place and don’t venture too far without saving first. You never know…