Joe Marchese has an article over at MediaPost, where he explains that the widget is not an effective marketing or advertising strategy, at least not by itself.  While you might initially question why I'm linking to a post thats seems to splash cold water on widgets, his thinking almost exactly squares with our own mantra at NewsGator Media & Consumer Products.  His comments, which I agree with, don't discount widgets offhand, rather they affirm the need to step back and take a look at your current marketing strategy before you (blindly) launch a widget campaign.  He says,

"The widget is not your strategy. Making the widget itself central to your strategy would be like saying that video is the center of your strategy, which begs the question; "Great, now what?" So we are going to make widgets; what widgets are we going to make? How are we going to distribute them? Why would people take them? Why would people share them? What do we hope to gain by getting people to use them? How are we going to measure success? These are the questions that will keep agencies gainfully employed for the decades to come -- at least, those that figure it out."

These points very much reaffirm one of the best practices that we tell our clients: don't develop a "widget strategy"; instead, determine if widgets hep you to achieve your the objectives and goals in your existing marketing plan.  If they do, then figure out how to implement widgets into this plan to further these goals.  In short, Joe is absolutely right that you should definitely think about some of the questions he mentions above before embarking on a widget campaign.