Twittley acts like Digg letting users vote up links submitted through the site. While there are some categories across the top, the popular, new and upcoming areas are where you see the trends and memes.
You login with your Twitter information and they provide a bookmarklet to ease your submissions. But the real power comes through the voting of the links and stories.
To ease submission to their site, they also offer a widget for your own blog to let readers submit your entries. If more people used the site it would have greater value to see what was important.