User blog comment:Lancer1289/Mass Effect, RPGs, and Gameinformer/@comment-899316-20101020222105/@comment-730941-20101021062327

I wouldn't say the DLC packs have a chronological order per se, other than the image used in the article for ease-of-reading purposes.

As for the Storyline page, most of them are somewhat irrelevant in terms of story, except perhaps for LoTSB - and until we know how many, if any, further 'bridging' DLC between ME2 and ME3 are in the works, it would be a bit difficult to find a place to add LotSB.