agreed, could be a limitation in ram or just overall processing power that the A5 is not capable of handling the new interface, such a shame but i guess it is what it is.
one question, the new apple tv 4 can be controlled with a harmony remote ?(IR) , because i read the new apple tv 4 remote uses bluetooth and my harmony remote is only IR
ATV4 has Bluetooth and IR, don't know if it works with Harmony though.