Your quiver now stays on with a bow or crossbow. A quiver is worn on your back, not held, so equipping a bow no longer takes your quiver off (and equipping a quiver no longer takes your bow off). Its Aim and critical-hit bonus now count while you shoot.
Other two-handed weapons still take the quiver off. Greatswords, staves and other two-handers swap it back into your satchel, as before. A quiver can also be worn with a one-handed weapon.
Tooltips tell you before you swap. A quiver's tooltip says it is worn with a bow or crossbow, and any weapon or off-hand item that would take your other hand off says so ("Equipping takes off your ...").
A stowed bow no longer clips through the quiver on your back. The bow rides a little toward your left shoulder, the crossbow a little further out.
