If this article is in fact true, and I have little reason to doubt it, this could have far-reaching effects around the world. It's not only Israel fighting groups using terror tactics, the US and the British are encountering the same thing in Iraq and Afghanistan (and killing a heck of a lot of civilians in the process). While at the moment only Israel is being condemned for trying to fight such groups, it is only a matter of time before the same condemnations will be heaped on the US, the British, and any other countries who tries to fight against people who use human shields, mosques to store weapons, etc. If Israel's hands are tied by the world courts, then the terrorists truly win, because Israel would be strictly forbidden to fight back against these fighters without harming civilians, a requirement made impossible by the use of human shields. If countries who fight fighters using terror tactics continue to be condemned, then such tactics will only be encouraged and far more people will die.
From a realistic point of view, though, I don't see the Israeli movement making the change. Israel does not have very many friends left in the UN, and the US and UK would much rather the world condemn Cast Lead than the war in Iraq, despite the fact the the war in Iraq was started for much worse reasons and killed many times more innocent people. I hope I'm wrong and the world changes to accommodate the new, more immoral ways of fighting that have sprang up since World War II, but I don't think so. We'll have to stay tuned for developments on this movement.