Your site really needs some redesign prior to SEO, imho.
1. Your site is NOT easy to navigate. Compare ssupload to imageshack. People who want to use a service like yours need to actually meander through a home screen of text, click on the upload link, then meander through the same text again to scroll down to the upload dialog box.
2. It's not immediate to the user what your site is for and what function it serves, compared to imageshack where it is VERY clear.
3. You require a valid login prior to displaying the upload dialog. This is a major turnoff to the potential users. You are much better off putting the login dialog front and center on the splash page. When the filename is entered, if the user is not already logged it, then hit them with the join page if you must.
These 3 suggestions are a few of the many ideas I have to improve your site's potential stickiness. If you would like a full analysis, PM me and we can work together to improve ssupload. This should be done in conjunction with any SEO, which I can also assist in.
PM me for more details.
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