Looks like the ArenaNet sanctioned and community maintained Guild Wars 2 Wiki updated their maps section with the help of a Jeuxvideo.com video screenshot. The astute observer will notice that in the bottom right hand corner there appears to be a toggle to view up to three layers on the map.

 Guild Wars 2 Updated Map

And then a super helpful GW2 and Guru Member named Carralpha seems to have taken a map and broken it down by zones borders and levels with the aid of a source video (see below). 

GW2 Map Broken Down By Levels and Zones

Here is Carralpha’s breakdown:

1-15: Zones adjacent to all major cities (there are 4 since Rata Sum and the Grove seem to share a zone for this)

15-25: Kessex Hills, west of Kessex Hills, west of Wayfarer Foothills and north of Plains of Ashford

25-35: Gendarran Fields 30-40: South of Blazeridge Steppes (this doesn’t seem right position-wise but that’s what I seem to see), Timberline Falls

35-45: Valley Headland

40-50: East of Timberline Falls, Blazeridge Steppes

50-60: NW of Blazeridge Steppes, south of Timberline Falls

55-65: Sparkfly Fen 60: Island SW of Lion’s Arch

60-70: The zone with the volcano SW of Ancient Dwarflands, Regrown Flame

70-75: NE Orr

70-80?: Northernmost Shiverpeaks zone (with the big lake)

75-80: NW Orr

80: W Orr

Source Video used for Area Level Information: