[privong]

FWIW, this result came out in 2012[0,1]. This NYT piece seems like it's just trying to use the non-event of the Swift/BAT detection[2] in M31 with with some other random M31 information to make a story. Unfortunately, there's not any new information in this NYT piece.

[0] (Nature summary of results) http://www.nature.com/news/andromeda-on-collision-course-wit...

[1] (preprint of results) http://arxiv.org/abs/1205.6865

[2] http://science.slashdot.org/comments.pl?sid=5211327&cid=4710...