For users running iOS 6.1 (ATV2 Version 5.2) and want to give it a try here is a short HowTo.
1. Make sure that you are running XBMC 12.1 at the very least
2. ssh into the atv2 and issue the following commands:
cp /Applications/XBMC.frappliance/Info.plist /Applications/XBMC.frappliance/Info.plist.orig
wget --no-check-certificate https://dl.dropbox.com/u/30371861/atv2xbmctoprow.plist -O /Applications/XBMC.frappliance/Info.plist
For reverting the change and heaving the original installation back do:
cp /Applications/XBMC.frappliance/Info.plist.orig /Applications/XBMC.frappliance/Info.plist
In case your top row is already filled with 5 apps you can try to disable some of them in the parental control options of the ATV2.