User blog comment:Arbington/New ME4 Teaser Pics, Possible Upcoming Reveal/@comment-1679409-20131114091848/@comment-1786741-20131115054225

It was actually more like one year along with a few months, considering the VGAs are basically at the very end of the year (mid December) and ME3 was released early 2012 (mid-March). ME1 also probably had a bit of development before it was announced