The Program will install the 64 bit plugins and I believe you will
just have to drop your license files in the folder with the plugins...

I keep my license files backed up in case of emergencies...

That's all an assumption, but would seem logical...

As much as I like the Mixbus extra plugins (I bought the complete v2 last year), I am just ordering the $40 update, and not getting their  Lookahead compressor.  Not that it is not a good deal, but I have other compressors with this feature already that do that.  BTW, I did finally get my email.  So now it is off to ordering v3 and relearning my way around Mixbus workflow. 

I can't bring myself to jump into MB at this time but I do like the concept of a tailored sound based on a very popular analog console. I played enough studio drum sessions with a Harrison board in my day.
 
However, I have been enjoying the H-EQ from Waves that helps me apply different sounding EQ's to tracks which gives me insight into what other console EQ emulators sound like. It's all good and refreshing. 
Maybe someday I will try out MB product but for now, I am happy with my DAWS and 3rd party EQ's.

Got my e-mail and placed my order this morning. I'll install it tonight. Good times!

Got it this morning! I just did some quick down and dirty testing. At first it was crashing quite a bit but it seemed like the more I restarted it the program ironed out and the crashing stopped. Almost like it was settling in. I am on Windows 7 on desktop and Windows 8.1 on laptop.
I have to say that it is a welcome change to have midi instruments now! I have had no issues with the midi controller at all.
Now I just have to learn the midi side of this thing a little better and it should be a great tool in the bag. And with a resounding NOOOOOO! I say you will have to pry Sonar from my cold, dead hands! 
BTW, there is NO NOTATION in Mixbus 3! hee-hee

Well without Notation in MB3 there will be no extensive Notation Fixes freds on the MB forum.

hmmm. I'm stuck at work and I'm waiting to get home and install MB3. Have any of you had luck getting melodyne to scan? I never got the 32bit to scan.
 

Have not got to melodyne yet. I've been scanning for about an hour and it keeps kicking things out that I know are valid 64bit vsts. I need to research how to look at what was black listed and see if I can fix them somehow.

Since I only ever experimented with MB2.x I intend to completely deinstall it before I install MB3 64bit.

bapu
Since I only ever experimented with MB2.x I intend to completely deinstall it before I install MB3 64bit.

I asked Harrison about that and received the two answers below:
 
Hi Rick,

 
Yes, you can do that if you like but just be aware that if you were previously running 32-bit Mixbus (on Windows presumably?) your plugins will all be 32-bit as well.  They won't work any more until you obtain 64-bit versions.  If you've got any important work in progress, it might be safer to run both versions in parallel for a while until you're confident about changing over permanently.
 
I highly encourage you to keep v2.5 installed to work on your older sessions.  There have been some changes to the signal flow of v3 that will change the sound of your old sessions.  And a few features  (such as channelstrip eq/compressor automation) are not carried over from v2 to v3.
 
I'm in the same boat as I only had one project that had been committed to MF2.5 and has since been captured in other places. I am now wishing that I would have removed 2.5 before installing 3.0