Partially correct, though Morro (now Microsoft Security Essentials (MSE)), is currently in beta test. Many here are already trying it out, see these new forums for more discussion if you're interested:
All OneCare subscriptions will continue to be supported through the end of their terms, while those about to end right now are being offered a free 6 month extension. So definition updates will continue, but the program itself is unlikely to be changed significantly in the future.
For more see the following including the links within the announcement:
I have uninstalled OneCare ready for hte move to Windows7 but what happens if i need an old file sometime in the future, how do i retrieve backups previously done under OneCare? Windows Backup and Restore doesnt 'see' the backup file. What program can i use?
The easy way would be to reinstall One Care and restore your backups to a folder, then after installing Windows 7 drag and drop the files where needed. The other option is to unzip the files with a utility such as WinZip. You can join any split files using this utility - http://www.freebyte.com/hjsplit/
Jim - MVP Windows Live - Forum Moderator - Live One Care - Live Mesh - Microsoft Security Essentials