Team Dignitas has posted an excellent infographic comparing your Season 1 rank (and MMR) to the league you will likely be placed in for Season 2.
Team Dignitas on Twitter
Updated infographic showing @PlayOverwatch Season 2 ranked divisions & associated S1 rank! http://team-dignitas.net/articles/news/overwatch/10086/overwatch-season-2-ranked-divisions ...pic.twitter.com/n0vLH1Drrc
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