I think the Product Hunt attention helped more than HN, but I've learnt that it's the longer term sources you don't expect that help the most. For example, it got into in an ArchDaily.com article that they re-publish every so often. That's easily been the most valuable source.
It's been growing pretty consistently for quite a while. About 5% every week.
To me the site looks fine, not ugly by any means. It's spartan/simple and utilitarian, as it probably should be. Will definitely be trying this out the next time I need a bulk-resize.
Is there any particular method you plan to use to turn a profit from this? Premium plans/etc.?
I feel that it's a difficult site to monetize. Part of the appeal is that it can be more convenient than having a resizing application on your computer. I think adding sign in (a dependency for premium plans) would undermine that a bit.
At the moment, it's still growing quickly, doesn't take up much of my time and costs barely anything to run. Given those circumstances, I don't feel I need to rush into monetizing. I'd rather wait and see.
Probably the best thing that could happen in the meantime is widespread adoption of a very low friction micropayments platform. I think PayPal or bitcoin are best positioned for that, but I haven't seen any signs of that ideal scenario coming to fruition any time soon.
Drive traffic to something else: That's my current thinking.
Adwords: I think Adwords would make the site seem slower and ruin it a bit. I'd consider a single, short text snippet Amazon link, though. Eg. "Check out the latest Nikon DSLR on Amazon"
Micropayments I would only consider if a service emerged that was as simple as embedding a one-click button and took sufficient market share that it wouldn't be a barrier. I can see that the likelihood of this in the near future is small, though.