Yep, these are the words that came from director Michael Mann — he just twitted this, and with a picture from the famous and well-crafted robbery that we all remember. Although this is not a surprise, this is the first time Mann is actually confirming the upcoming sequel. No timeline has been declared yet, but “Coming soon” is…coming soon.
Source: Michael Mann: “HEAT 2 is coming soon” – Y.M.Cinema – News & Insights on Digital Cinema