I average probably 30-40 at a time that I just leave open. It'll go up or down depending on if I've read what they contain and see fit to end their meager existence. I browse all forums in new tabs, and close them when I'm done typically. Same goes for news stories as I generally dislike the constant loading of using the back button. I also despise using bookmarks because I either have to open a bookmark menu and find the one I want or leave it open all of the time and I refuse to waste the screen space on it. Tabs are simply faster and easier.