Itachi is free from Kabuto's actual control but is still "alive" because the Edo Jutsu is still in play. Since Itachi was summoned at the very beginning with everyone else once Kabuto cancels the Jutsu Itachi himself would probably be cancelled too. If it doesn't work that way then what?? Itachi would forever be alive as a zombie?
Why do you think he can only summon and de-summon them all together though? Surely he could control every one of them individually, which is why he could also summon some of them later on as they were needed, instead of summoning them all at once at the start of the war.
Getting him under genjutsu is exactly what I mean by beating. I don't think Itachi would waste even a second talking to Sasuke when he could immediately break the jutsu and potentially save many lives.
On yet another note, Kishi will be directly involved with the story and character designs of the next Naruto movie, due out in Japanese theatres July. Poster, with open-jacket though crazily over-confident Hinata:
Hmmm, Naruto's jacket is open too..... OHO, OHOHOHHOOHOHOHOHOHOHOHOHOOHOHOHO
NICE, Hinata looks sexy, sexy in that picture.
"I got rid of my teeth at a young age because... I'm straight. Teeth are for gay people. That's why fairies come and get them. "