Here's a shocker. According to a report from IDC, if you're going to do a "preroll" video ad that plays before the content a cell phone viewer selects, make sure it's not too long. Otherwise you risk losing the viewer before the actual content even gets started.

The reason? Cell phone viewers aren't generally a captive audience, the way they might be if they're tuning into the latest episode of, say, Lost on regular television. The IDC report found that the limit is somewhere between 8 and 10 seconds.

IDC Says Don't Underestimate Full Potential of Mobile Marketing (IDC via MocoNews)