Yes. I'm on the same PC that I've been testing all the previous builds with. And I did a clean install last night (after having done an upgrade once before that). Once I signed in with my Microsoft account, I activated fine without ever entering a key. And I'm no longer receiving insider builds.
Mine worked just fine using the Upgrade method. I installed 8.1, and successfully activated it using my TechNet key. Next, I did an upgrad to windows 10 using USB, and chose the option to keep nothing. When prompted for a key, I chose to skip the step. Once I signed in with my Microsoft account, Windows 10 activated successfully. And, just for the sake of knowing if it would work, I then took it a step farther and did a clean install from USB. Again, I skipped the step where you are prompted to enter a key. And again, after signing in with my Microsoft account, I had an activated clean install of Windows 10 Pro.
I had somewhat similar issues with my GTX 550 Ti. After a clean installation from USB, and a couple of restarts, I looked in my Windows Update installation history and saw that the Nvidia driver update failed. (Interesting and annoying sidenote here: as far as I can tell, if a driver update via Windows Update fails, they give you no way of restarting that failed update. Grrr.) I looked in Programs and Features to see if the expected NVidia Graphics Driver, 3d Vision Driver, etc. were listed there, and they were not. However, Device Manager did show that I had a working GTX 550 Ti under the Display Adapters section. I eventually went to the Nvidia site, got the latest driver and ran the install, which worked for me. If the suggestion above doesn't work out, you might also try going in to Device Manager and uninstalling the card completely, selecting the option to delete any driver files, then reboot and allow Windows to pull a driver from its Update servers.
Please check to see if your speakers are plugged in and powered on.
Totally kidding there... just seemed like fun. I did the same thing... enabled the Windows Startup sound, rebooted, and nothing. If memory serves, it's been that way through most of the Insider builds along the way.