Looks very nice. Also, I like the scaling touch: the use of full-size buildings across the map (as opposed to 'mini-town') plays across two usually-exclusive ideas - that this isn't a continent, which that much landmass would normally suggest, but neither is it a town, as the buildings might otherwise imply. Between the two, they do a great deal to help sell the concept of 'island'. Well done!
Although I do now wonder about the sanity of whatever forester maintains that stand of trees just across the river east of the icy zone...
Edit: Also, if it won't be a plot spoiler, what's up with that weird grayish river, and the little area it lets out into? Those look strange.