- Advanced Integration of Steinberg's new hardware
Designed especially for Cubase by Steinberg and Yamaha, and precision-manufactured by Yamaha to the most exacting standards, the MR816 CSX and the MR816 X represent a new generation of solutions for musicians and producers. Together with the CC121 Advanced Integration Controller, MR816 CSX and MR816 X combine with the Cubase 4.5 to provide an all-round system solution of unparalleled flexibility and power.
Pioneering technologies developed for this unique new system move beyond traditional software/hardware paradigms, and offer a range of exciting new advantages for anyone recording, mixing and producing music.

- Improved support of Yamaha Hardware:
Yamaha MOTIF-RACK XS / MOTIF XS6/7/8 integration : Completely new and extended support for the MOTIF XS has been added to Cubase 4.5
Yamaha KX25/KX49/KX61/KX8 USB Keyboard support

- VST Sound
Steinberg's universal media management format – VST Sound – is a fundamental part of VST3, the latest version of Steinberg's industry standard Virtual Studio Technology.
By supporting VST Sound , plug-ins and instruments from third party manufacturers can be directly integrated into MediaBay – the media management system used in Steinberg's host applications. This integration makes the entire process of finding and working with any form of media file including audio, loops, VSTi presets, videos, MIDI parts and Track Presets, much faster and simpler.
VST Sound replaces SoundFrame, which was incorporated into previous versions of Cubase products.

- VST Sound Collection Vol. I
The VST Sound Collection Vol. I offers over 1.5 GB of new content, sounds and loops produced by top producers, including Yamaha, Sonic Reality and Big Fish Audio. It can be used royalty free by all Cubase customers.

- Sequel 2 and Sequel Content Set support

Officially compatible with Mac OS X Leopard (version 10.5)
Bug fixes.

Bug fixes....