Agree with cake. Maybe change the white to some kind of Bone white or something (#E3DAC9) and a darker grey for a background. Otherwise it's great, very manageable.
You might want to edit the tumblr skin and strip the posts of the date, and maybe title the sections instead. Basically if you are going to use tumblr in a non blog format, I would strip the bloging elements as much as possible. Unless you plan to update often, its going to look lame in January when your sections have huge banners that say they are from November of last year. Otherwise I think it works surprisingly well!
I think your page could benefit from having more of a focal point. Like have your best piece be part of the header or instead of many thumbnails have at least one larger one. Something to draw you in more instead of having the user choose which thumbnails to choose right away.
Posts
If I were going to be picky I would say the grey background, white windows, and brown buttons aren't really cohesive.
oh, and hit the follow button, cause I'd love to see more!
Uncanny Magazine!
The Mad Writers Union
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