Let's use an analogy to discuss virtual trade shows in business to business (B2B) Marketing Communications.
In the old days, if you wanted to meet several vendors, meet industry movers and shakers, and kick a few tires, you had one option: go to a trade show (exhibition). Analagous to that ... in the old days, if you wanted to speak with someone far away, you had to use the phone. No other choice.
Funny, we don't find ourselves debating Skype vs regular phone calls, or regular phone calls vs. SMS. When it comes to the phone, we simply integrate all the options into our lives and use the mode, or mix, that best suits us. But we do get into interesting debates on the virtues of traditional trade shows vs virtual events. There's no need for the debate.
Sometimes attending a traditional trade show is not feasible. For example, you may have a commitment in a different location, or you may choose to not spend the money attending it. In such a situation, your choices are: 1) no participation at all, 2) virtual event, or 3) call a hundred vendors and interview them. Or, maybe the show exists only in virtual form. You can choose to: 1) not participate, 2) learn what you can in a virtual environment, or 3) call a hundred vendors and interview them.
Next time the topic arises, remember: you have options and choices (just like you do when it comes to communicating with people). Don't make it a debate, make it a choice - a choice of how you are best served when collecting critical information.