Almost as soon as event organizers began to see the value of using hashtags to organize tweets related to an event, applications began to pop up to make the information sharing more user-friendly. Thus, we've seen Twitterfalls, hashtag archivers and tweet curation platforms with varying degrees of adoption by event professionals.
I've always hated networking events. The premise always seemed awkward and ugly to me. An event held so that strangers can meet and attempt to sell services or products to each other.
Of course, the whole reason you started using social media is because you heard what a wonderful tool it is for marketing. And as an event planner or producer you want to milk it for all it's worth.
Have you considered your face to face event objectives in light of the growing popularity of remote attendance and virtual events? More and more it seems that events that have done this are achieving success and getting rave reviews.