Debian Sid - migrating to Systemd?

When I run an aptitude full-upgrade, I am prompted to remove sysvinit-core and replace it with systemd-sysv. does this mean that Debian Sid is making the transition now, or is it the result of the specific combination of packages that I happen to have installed? To be clear, I want to make the change to Systemd, while minimizing the risk of an unbootable system in the transition, and I'm considering whether now is the time to go ahead with it or not.