It's a great show, largely because of the cast I think though many of the story lines are well worth watching, too. The main cast is presented as an odd sort of tight "family" and each character is different but endearing in his/her own way. The character Ziva is a compelling and always interesting, larger than life woman, formerly of the Israeli Mossad with amazing skills. Cote de Pablo who portrays her will leave very big shoes to fill.
I don't like the promos they are running, promoting her departure. It's sad enough that she's chosen not to continue with the show and I feel like they might be giving away too many spoilers.