This first release of MC 24 is very nice indeed (64-bit version). I don't have an HTPC setup, so I don't use the remote and TV tuner features of MC, which seem to have been the focus for improvements in the past couple of years, so in the past I mostly upgraded to support JRiver.
This new version has a nice, clean default UI (long overdue). I haven't checked out the skins yet, but I don't think I'll need them. The entire UI seems faster and smoother in operation. Scrolling through my large movie collection in Thumbnail view feels just right now, not too fast or slow. The addition of Streaming to the nav tree is very welcome--saves a few clicks.
Best of all, though, is Hendrick's new Blu-ray menus feature. There were some problems with 24.0.14, but they're mostly gone in 24.0.15. I can finally get rid of PowerDVD, which I only kept around to access the menus and extras. Although I have a 4K display, I don't intend to upgrade to UHD so the lack of menus there isn't a problem for me.
Congratulations to the development team for a very impressive start. I'm looking forward to whatever refinements are coming in the next year.