With Israel banning the media from Gaza, it is hard to come up with firm numbers for those killed in the present Israeli attack, but at the moment it seems to be more than 700 Palestinians, including in excess of 200 children and nearly 100 women. About ten Israelis have been killed. Of course, the Palestinians are used to casualties. Israel killed more than 400 last year, a similar number the year before, and more than 600 in 2006.
Although we hear a great deal about the threat of terrorism, states and governments tend to kill many more people, and those who claim to be trying to avoid civilian casualties, e.g. Israel, tend to kill and injure far more than those accused of deliberately targeting them, e.g. Hamas.