I have over 150 items now, and average around 500 - 600 views per day at the moment. I would suggest:
- SEO!! so key, keep reading, plugging away, tweaking and so on.
- backlinks: I think google 'likes' these, so put a link back to your shop in every listing, as well as a link to something else your viewer 'may like'. This also encourages people to click around your shop, meaning more views!
I think these things have worked for me :-)