Its a totally new menu system which needs to be learned how to use again.
Your box will now work independently from an internet connection.
The Menu system is based on thumbnails which involves scanning through them to find out what they refer to - switching to list view involves scrolling down through many lines of info (with no page down).
Just about everything stops if you lose the internet even for a second or two - the box often fails to re-train and requires a re-boot.
The Sony BD player has no trouble (eg running iPlayer in HD at 6.5Mbps even after the BT Vbox has failed to re-train) The old software (on the same box) managed to download 8 HD films in series in one queue - with the new software it has failed to download any after about 50 attempts.
"Random" re-boots seem to occur at just after 3pm, 6pm 9pm etc. - or soon after an HD download is attempted.
"Try again" has never ever re-started a download.
PS when I tried MultiRoom (Companion mode) the second box became a slave and you effectively only had one recorder.