I definitely don't remember seeing many balls hit to that part of the ballpark.
According to the indispensable ESPN Home Run Tracker, that is the longest homer at Fenway Park since July 30, 2006, when Vladimir Guerrero hit a 484-foot bomb off Curt Schilling. Unfortunately the MLB.com video of Vlad's blast is long gone, and YouTube is of no help, so we'll have to leave that one to the imagination.
Ortiz's blast was the second longest home run hit this season, behind this 484-foot dinger by (who else?) Giancarlo Stanton.