Lord knows our friends in Israel don't need any more terrorists gunning after them, but I actually view this as a very positive step in the war on terror. Not only did Iraq - once a safe haven for al-Zarqawi - turn against him, but now (assuming this report is true) he's setting up for a war on Israel. It's kinda hard to keep a low profile while recruiting jihadists, training them, moving weapons, etc. Although he did very well in operational security in Iraq, I think much of the insfrastructure was in place long before American boots were on the ground. I think this time around he'll be more vulnerable, especially given that so many terrorists streamed into the roach motel (aka Iraq), never to return.
As we have seen time and time again, the Israelis have stellar counterterrorism intelligence. They are combat hardened and well armed, and the operational area through which one can wage war on Israel is significantly smaller than in Iraq. (Although they will likely have long-range rockets compliments of Hezbollah.)
Not to mention we have about 100K American troops just itching for some payback, that could open another front in such a war.