30 seconds.
Clean first, sanitize second...Iodophor is the concentrated Iodine sanitizer we're talking about here. Star San is not iodine based and is the other most popular sanitizer around...Both have a 30 second contact time and shouldn't be rinsed afterwards.
Oxyclean and the generic derivitives are the best cleaner around even better than PBW...most of the people on here use it...and since I started using Oxyclean, I've never needed to use either a carboy or bottle brush, the bubbles break up even the toughest gunk inside a fermenter or brewpot.
Just make sure you rinse thoroughly afterwards.
Ive heard about it on these forums, do you mean the stuff Billy Mays sells on tv?