We're going to rely on the wisdom of the crowd to answer this question: which, if any, of the year's tech conferences is a must? They all make great claims. Demo is an institution; Techcrunch 20 is like Demo, only less corrupt; David Hornik's new event, The Lobby, cuts out the boring panels; and Always On's Stanford Summit will be "Silicon Valley's most powerful gathering." And, if you believe that, I have a $3,000 conference pass to sell you.