Eboue hasn't played much because Sagna has been brilliant for us this season and has replaced him as our RB, he is a strong gritty defender and unlike Eboue is very committed defender and gets is good in the air as well. On his day Eboue is sensational as RB but the guy's work ethic leaves a lot to be desired at times.
So Eboue is out because Sagna's better and Sagna's out because he's only played this season and hasn't impressed me. His positional sense leaves a lot to be desired and Wenger hasn't had chance to smooth him out yet. He seems talented enough but he's still raw.