Shortly after Anonymous declared war on the Israeli internet, a separate group of apparently Pakistani hackers has defaced at least two Microsoft-run websites. Visiting the Israeli versions of MSN and Bing brings up an anti-Israel diatribe "on the behalf of all Pakistani and all Muslims," promising that "your war on Gaza will make you cry blood." The Israeli Skype website, meanwhile, is unavailable. Though the ideological justification is similar, this doesn't appear to be related to OpIsrael, an Anonymous-affiliated offensive meant as payback after Israel threatened to cut off internet access in Gaza. Instead, it's credited to a number of hackers, including ZombiE_KsA and the Pakistan Cyber Army.
Both ZombiE_KsA and the Pakistan Cyber Army have apparently been active for the past few years, and the page was partially copied and pasted from previous hacks, including a 2011 attack on the Supreme Court of Pakistan's site. A hacker who claimed affiliation with the Pakistan Cyber Army also defaced about 80 small sites during the Innocence of Muslims controversy in September. Such hack-based protests have garnered publicity for years, but the current conflict in Gaza has been particularly shaped by its online components: both Israel and Hamas have taken to social media to push their respective causes, with Israel tweeting and liveblogging its ongoing attacks. Both MSN and Bing are major sites — arguably bigger than anything Anonymous seems to have managed so far — but the hack seems like almost a sideline compared to the propaganda ware being fought through official channels.
Update: While MSN and Bing are accessible through the alternate "il.bing.com" and "il.msn.com," the "bing.co.il" site remains defaced. MSN's site, however, seems to have been counter-hacked: visiting "msn.co.il" now brings up the Borat trailer with the text "How 1337 pakistani looks like."