virtualbox[.]org
I probably wouldn't have posted about a new V/Box version except the last line in the Changelog says:
Windows Guest: Introduced Windows 11 guest support, including unattended installation
Don't get your hopes up.
Install the upgrade when you're ready, if of course you want to, but the extent of Win11 support appears to be Win11 now showing up in the list of guest OSes supported. The TPM support that's rumored to arrive with v.7 is not there. The V/Box BIOS settings don't have anything relevant. The Insider Win10 VM still shows the VM is not qualified for Win11, & the Win11 VM shows the Windows version number as 21H2, same as that Insider copy of Win10.