According to Websters New words and Slang
embiggen
(verb) : to enlarge (as an online image) for better viewing
Submitted by: Lynne Meinen from Illinois on Nov. 03, 2009 10:33
(verb) : to make large or larger
Submitted by: Natasha Gilmore from Washington on Jul. 06, 2008 10:54
(verb) : to make bigger
A noble spirit embiggens the smallest man. —The Simpsons
Submitted by: Conan the Grammarian from New York on Aug. 31, 2007 15:32
So it's entered the pop-culture lexicon (like the word "Douchebaggery" which I'm pretty sure I invented) but it's not an official word.