+ Use more than 4GB RAM
+ Use high precision 64bit numbers in Max messages
+ Load 64bit Audio Unit and VST plugins
Live 9 support:
+ New devices
+ New Live API features
+ Performance and stability improvements
New Gen Features:
+ Integrated operator reference
+ New operators and expression features
+ (Beta) Export Gen code to C++ (gen~) or GLSL (jit.gl.pix)
+ Faster application launch
+ Faster patcher load time
+ General optimizations
64bit application support is a big deal, and given how long Max has been under development in a 32bit world, it was no easy feat. Thank you all for your patience as we've worked to make this happen. 64bit applications allow users to take advantage of a much larger memory space and hence more than the ~4GB of RAM we are limited to under 32bit. We've also been able to make infrastructural changes to support 64bit numbers when passed via Max messages for higher precision calculations. These two things are features you have been requesting in Max for years, and finally those features are here.
However, we'd like to balance expectations here. Since this is our first 64bit release, we will not have all of the features of the 32bit version, especially regarding Jitter and QuickTime support. QuickTime is simply not available on Windows under 64bit, where we will rely on DirectShow for movie playback (to playback QuickTime files you will need a third party plugin for DirectShow). Apple's QTKit API on Macintosh 64bit has fewer features than the 32bit version of QuickTime, and requires a dramatic rewrite of our code base. We've only implemented the most basic of functionality for movie playback at this time on both platforms. We will be continuing to work on Jitter video playback and other QT features in the 64bit version, but many features are not present and may not make it to the 64bit version ever.
Max and MSP should have nearly all the same features, except where it relies on QuickTime (e.g. PICT files are not currently supported under 64bit and instead we recommend converting to PNG or JPG). However, 3rd party developers will need to port their objects to 64bit for them to be able to run inside the 64bit version of Max. There is no loading of 32bit externals in 64bit version of Max.
We will be providing an SDK for 3rd party developers in the coming days, but it will likely take some time before any particular 3rd party external will be available to use. We would recommend that if you do want to use the 64bit version and you have 3rd party dependencies that you see if you can remove these dependencies by using core objects or abstractions to replace these dependencies, until your favorite 3rd party object is available.
On Macintosh, the application comes as a single FAT bundle, by default set to run in 32bit mode. To run in 64bit mode, select the application and "Get Info" from the finder. In the "General" tab there should be a check box which says "Open in 32-bit mode". You can turn this off to run in 64bit. If you want to keep separate 32bit and 64bit versions, you can duplicate your max folder, select one of the applications and set it to run in 64bit as described. Externals are also FAT bundles--i.e. contain both 32 and 64bit code.
On Windows, there are separate 32bit and 64bit installers and applications, and externals are in separate .mxe (32bit) and .mxe64 files.
Max for Live users will need to use Live 9 in conjunction with Max 6.1. Live 9 will be released on March 5th, and as you may have heard, Max for Live is now included in the Live Suite bundle. The factory content will look a little different than in previous versions and you will need to download and install the appropriate live packs for the content which previously was installed by default. In addition to the exciting features of Live 9, there are some great new devices in Max for Live, especially the drum synths and convolution reverb, but I will recommend you go to the Ableton.com website for more information regarding Live 9 and Max for Live.
New Gen features:
Gen has some significant additions and improvements in this release. Gen now has an integrated operator reference in the side bar to make learning and discovery easier than in previous releases. The operator set has grown, and the GenExpr language now supports recursive functions (for CPU, not GPU targets), calling gen patchers as functions, and defining functions with named parameters. But most exciting in this release is that we have a beta version of code export. This means that you can take your gen~ patchers and export them to C++ code and your jit.gl.pix objects and export them to GLSL code. This feature only has limited support in our initial Max 6.1 release, but over the coming months, we will be working to improve the generated code, template examples, and documentation to make this feature useful for those of you who have been waiting for this capability. Note that the code export feature will assume that you are familiar with C++ and working with a development IDE like XCode or Visual Studio. We will be adding more code export examples and documentation in the WIKI at https://cycling74.com/wiki/index.php?title=Category:Gen_Code_Export