To Todikovic: no you don't need to install the SU toolbar, but it does make your life easier if you do. It's quite easy to give the "thumbs up" and review a site with the buttons easily at your disposal. I have the toolbar installed, but keep it disabled most of the time. I only enable it when I need it.
I've been using SU for the last two months (go back a few pages in this thread to see my posts) and it's generated some traffic for me. In total, I've gotten 517 hits from SU since I started back in September. It's not that much, but who knows, maybe I found a few repeat visitors through the site. I think the key to advertising any website is to use many different techniques in combination. StumbleUpon is not a magic bullet, but rather just one way of many to get your site known. It's also a great tool in which I've found a couple of interesting websites. Using the Stumble feature is a lot of fun.
I don't actively promote my site through SU anymore, as my site has grown and I receive many more hits from other sources now. But if you would like me to stumble each others' pages, send me an email through SU with the site info and give me a couple of days to respond
btw, here are two very important tips about SU:
First, if you are doing a review for a site, remember to fill in the keytags (the more the better). A thumbs up and a good review ain't going to do much if it's not in any category.
Second, a website can be stumbled multiple times. Each page inside a website can be stumbled separately. That's in case a website has a totally awesome subpage that someone feels is worthy of stumbling and should be directly visited. If you have an important subpage inside your site, stumble it as well. But don't abuse this technique either, you could get tagged as spamming.
