Wow, that was the easiest SONAR install I've ever done.  The Command Center is amazing for speed of download and install, no more entering serial numbers.  It was so fast I was sure that the install didn't work right but everything was good.
 
Sonar Platinum so far has worked flawlessly except when tuning vocals with Melodyne.  After adding a region FX and tuning one part of a clip it seems there are artifacts (skips and repeated vocal stutters) on parts of the clip that I didn't even touch.  This has happened a couple of times, I'm looking for a recipe to reliably reproduce it.  In the meantime if any of the other early buyers could check it out and see if they have any similar issue it would help to see if it's something particular to my setup.
 
It's not the kind of skip/pop/crackle you get from running with insufficient audio buffers.  It's repeatable and seems to permanently change the audio in the exact same spot (though of course undo or removing the region FX prior to bouncing returns it to the original state.)  I have set my audio buffers to max and it doesn't make a difference.
 
Other than that I'm really impressed with Platinum so far.

I forgot to mention that I have the full Melodyne editor version, not sure if that will make any difference.

I'm getting this as well on several Projects. Hope it gets fixed soon!

I'd love to hear from Cake about this one!
 
This might actually give us an indication of how fast those 'patches' will be released!
 

Not to hijack the thread, but I migrated to new Sonar as well, and every went swimmingly EXCEPT melodyne.  I can't get it to show up as an effect at all.  I owned essential before, got it from X3 as well and now have  it again.  I installed, I "reinstalled", I checked my various VST paths, but no love.  Everything else went great. Still shows up in X3.   Did you guys do anything special to get Melodyne in the new version?

I was under the impression that Sonar Platinum won't be available for download till January 21st. So how is it possible that you're using it?

Leadfoot
I was under the impression that Sonar Platinum won't be available for download till January 21st. So how is it possible that you're using it?

You could sign up for an "I'd like to get it early" e-mail. Some people (like me) got said e-mail. Dunno why they chose to do it like that, but there you go.

Cakewalk is randomly selecting users from the presale sign up here https://www.cakewalk.com/.oducts/SONAR/Coming-Soon

I'm an Aquarius, and all winter zodiac signs got the option for early upgrade.  Didn't you hear, or are you a freaking Leo or something??

CoteRotie
It's not the kind of skip/pop/crackle you get from running with insufficient audio buffers.  It's repeatable and seems to permanently change the audio in the exact same spot (though of course undo or removing the region FX prior to bouncing returns it to the original state.)  I have set my audio buffers to max and it doesn't make a difference.
 
Other than that I'm really impressed with Platinum so far.

Same here I can confirm the bug. I have the full version of Melodyne and the minute you tweak something there is crackling happening. Luckily there is Autotune to the rescue (and its amazing auto mode)