In commit http://cgit.freedesktop.org/systemd/systemd/commit/?id=26cbf29c52a36b6ad9d1ccc16d8f7adccefeddca some units were dropped that were intended to be moved to plymouth. However these units haven't been added to plymouth yet. This breaks booting with non-root encrypted file systems (e.g. swap or /home). While it is possible to manually work around this every boot, it is pretty inconvenient. Currently this effects Fedora rawhide which already has the systemd change.
Thanks for the report, it was a misunderstanding between Kay and me. Should be fixed now: http://cgit.freedesktop.org/plymouth/commit/?id=76d0db51c26fff42c03ccf89a8f84193aa95c03f
I tested the Fedora build (0.8.6-1) and am still seeing issues with getting the passwords. But I do see them getting asked for in places they weren't before. I am also still recovering from the recent dracut issue, so there are a couple of ways this might not be a plymouth problem any more.
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.