The announcement was made— naturally— by Twitter:
I’m thrilled to be joining Twitter -- and thankful for my time at Google. Both are more than just companies. They're movements.— Gabriel Stricker (@gabrielstricker) April 5, 2012
Google still lists Stricker as Director of Global Communications & Public Affairs, where he reported to Senior Vice President Communications Rachel Whetstone:
Gabriel Stricker is Director of Global Communications & Public Affairs at Google Inc. where he heads Search communications – addressing everything from web search and other search properties (such as Maps, Earth, News and Books) to issues pertaining to partnerships, content, and the use of intellectual property. Gabriel received his undergraduate degree from the University of California at Berkeley and his master’s degree in International Affairs from Columbia University. He is the author of the bestselling book on guerrilla marketing entitled, Mao In the Boardroom, published by St. Martin’s Press.
At Twitter, he is now called Vice President of Communications.