Even for Facebook, this is a big event.
Facebook itself says it's happy and honored to move into the area once occupied by Sun Microsystems.
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Local leaders are happy too. They are praising Facebook, saying they look forward to having all those Facebookers in the area.
No Zuckerberg here, at least not yet. All in all, Palo Alto's loss is Menlo Park's gain. Facebook brings a big -- and growing -- workforce, with huge potential for this area now to become a huge tech ho tspot.
Look for local businesses to put out the welcome mat - as long as e traffic doesn't increase too much.
Either way, Menlo Park has a powerful new friend.
Scott is on Twitter: @scottbudman