With the release of version 6.2, Titanium Backup should now play along nicely with Android 5.0. This means rooted users who have already jumped to Lollipop can continue to use the tool to back up, restore, or freeze whichever apps they wish.
When you install the app, it's not going to look pretty. There's no Material Design to drool over, nor are there any fancy animations to catch your eye. Even the icon looks a little out of date these days.