Channel 122. And...
-Virgin to move Sky 3 to Channel 180 on the 22nd of September.
-Virgin to move Sky 2 to Channel 123 on the 29th of September.
-Sky1 HD to launch on Virgin Channel 122 on October 1st.
-All Sky Movies and Sky Movies HD Channel to be made free to air for the weekend of the 30th of October.
(Thanks to MediaBoy for the additional info.)