We have a proper retail CD release of Super Mario Odyssey Original Soundtrack - four discs no less - coming up for release in Japan on Feb 28. It's currently up for pre-order at Play-Asia and the usual other importers.
https://vgmdb.net/album/73671 (no track list as of yet)

There's also a somewhat scantier digital release, Super Mario Odyssey Sound Selection, currently available on iTunes. It clocks out at 39 minutes with 12 tracks - four of which are "Jump Up, Super Star!"
https://vgmdb.net/album/73677

I'm sure several people here have played the game by this point. What were your thoughts on the music?

I've indulged in the glory of "Jump Up, Super Star" via gameplay vids and the sequence it plays in (something about the gameplay speaks to me...), but I have zero doubt this soundtrack is going to be amazing. The series has been on fire since the first Mario Galaxy, musically, so I'm purposefully staying away from the rest of the music to take in the soundtrack.

My lone concern is...do they have enough music to firmly fill 4 discs? Galaxy 1 and 2 and 3D World all fit snugly on two discs.

Both vocal songs were garbage (including when they were used in-game because that ending sequence deserved a Mario/Bowser medley infinitely more than some tritely written drivel, and the New Donk City Donkey Kong fanservice 8-bit platforming section was completely hindered by the song they used) but the instrumental soundtrack was pretty solid overall and generally fit the levels well. The chiptune renditions of the stage themes are great. I think the in-game sound test menu clocks in around 80 tracks, so I'm wondering how they're going to stretch that to fill 4 CDs. I'm guessing 3 CDs with the actual music and the 4th CD will be some kind of mini/bonus/SFX CD. Regardless, I'm eager to see the final tracklisting.

As far as my experience with Odyssey goes, I spent about 35 hours with the game and collected all 880 in-game Power Moons and bought most of the outfits. (Yes, I was dumb enough to buy the Skeleton suit.)

I got all the Moons and actually did the grinding necessary to get up to 999, so I've played a *bit* of the game...

Anyway, I'm pretty excited that this is getting a full OST release.  I imagine the four discs is to accommodate the fact that almost every area in the game has both a normal and 8 bit version.

Overall, I would say this is the weakest console 3D Mario soundtrack in a while.  It's certainly not BAD - far from it - I'm really looking forward to buying the album.  That said, the 3 hit combo of Mario Galaxy 1/2 and Mario 3D World is REALLY hard to top.  I also wonder what happened to Mahito Yokota, as he isn't even listed as a composer this time around.  He was still in the credits for production, but I'm hoping this doesn't mean he got promoted out of doing actual creative-level stuff as Kondo did. 

I concur with Qui-Gon that the soundtrack isn't up to recent 3D Mario standards. With a few notable exceptions (like Cascade Kingdom bringing back the orchestra of Galaxy), most of the music was content to be subtle. Not all that far removed from Breath of the Wild's approach, actually (although I like that soundtrack more).

Game was amazing, though. I got every moon but 2 of the most obnoxious.

I'll be honest.  when I learned this score was getting a release, I didn't hesitate.  I jumped at the start.  The last two big Mario 3D games (both Mario Galaxies and Super Mario 3D World) had CD soundtracks, but both were only purchasable from ClubNintendo and not widely available.  That this score is being released shows that Nintendo is having a change of heart with their game soundtracks, and that's just awesome.  I found this soundtrack to be great fun and almost up there with Galaxy and easily better than 3D World and 64.