hi I am allowing members to add javascript/html in their profileon the sidebar. Obviously this will allow all ads like adsense, ypn, adbrite and other ads on their network. Is this allowed by adsense? my site is this: http://www.ozucs.com
Well.... this is a very broad topic. However, It is allowed if you don't place any ads on your site. Only members will be able to place their ads. Don't place any ads if AdSense is already there. Don't place any other ads if YPN is there. So, in this way you can play safe. btw, Read AdSense TOS!
You can place ads assuming that the ad provider you choose will let you have (2) account codes on the same page--AdSense will NOT let you do this... so if you do choose AdSense, you would probably have to disable the AdSense code being inserted by your members.