I noticed that this build is very snappy at opening apps and for performing basic tasks. The random explorer freezes and expected UI bugs are absent. Plus this build does not force you into Insider Preview Builds (Just like any RTM builds) Ofcourse, this may not be the final 19H1 build but it's damn close. Kudos to Microsoft for flighting a good build after a long time. I am using this as my daily after skipping 1 month worth of utter trash builds. BTW all games are working just as they would. I don't use Creative Sound card junk so I am unaffected by it.
No more flashing (flickering) on taskbar pined icons. Try to delete files on desktop and than click empty the recycle bin, before icons flash like refresh or something, but no more !!! I see transparency issue in action center.
After installing 18356.1 (fresh installations) on a couple of computers with no issues, I then upgraded a laptop from 17763.379 to 18356.1. This laptop had VMware Workstation v15.0.2 running fine, but after the upgrade VMware Workstation does not run properly and it seems to have all sorts of problems, freezing, not installing new OSes, cannot boot into firmware, etc.. I uninstalled VMware Workstation and reinstalled; but no success. I then used repaire, it seems to have removed some drivers, now some VMs can start but there are still problems. Usually (for GPT partitions) there is 499MB, 100MB, 16MB and the main partition. This is now (with fresh installations) 529MB, 100MB, 16MB and the main partition. With the upgraded installation I now have 499MB, 100MB, 16MB, 631MB and the main partition!?. The CPU seems to fluctuate around 25% all the time on the upgraded machine. I am still investigating and hope to resolve this problem and will write about it if it is worth reporting; I will probably end up formatting and reinstalling.
I have formatted and rebuilt the computer with a fresh installation of Windows 18356.1, but the problem persisted, I could not install even Windows 7. However, after several hours of reinstalling my old applications and trying everything I know, the issue was resolved. What seems to have resolved the problem was that I reset the VMware Workstation BIOS while trying to install Windows 7. Click Edit Virtual Machine Settings --> Options (Tab) --> Advanced --> BIOS (under Firmware Type) --> OK, then on VM --> Power --> Power On to Firmware --> Load Setup Defaults (under Exit) --> Exit Saving Changes. OR if you have chosen UEFI on VM --> Power --> Power On to Firmware --> Reset the system I was able to install Windows 18855 without the CPU ID modification in the VMX file, I think Microsoft resolved this issue a couple of releases back on 20H1. I don't know what caused the problem in the first place, VMware Workstation might have inherited some settings from existing Virtual Machines, Linux, Mac OS, Windows XP, Windows 7 and Windows 10, which were made along the years on other machines using other versions of Workstation. The partitions are also back to normal after the format, I don't know what caused it, probably the Optane module!! A little indication that 18356.1 may not be the RTM is that it does not boot on VMware while Microsoft sorted this issue for 20H1.
If they don't find any last minute show stopper bugs, Mid April. If you are an Insider, then within next week or two.