I think it does, and has. When I have had webinars on my website, it has usually increased attendance at my next apartment association "gig" or when I have a general admission event in a market. I think the cross-marketing can be very valuable.
What I have found is a number of events are well-marketed online and even virally, but then they don't live up to the buzz by producing a sub-par event. Obviously people won't go back, regardless of how well the marketing people handle promotions the next year. Attending a show like TAA (Texas Apartment Association), FAA (Florida...) and Brainstorming certainly reinforces the idea that apartment events are no longer dull trade shows with four seminars off in the partitioned ballroom. They have to be fun, involved, engaging events with multiple ways to learn, connect, network and have fun. Few state or city events fit this bill.
But I also know that relying on Internet marketing only can be a mistake. When I first launched my business, granted 7 years ago is a long time, I missed a number of possible attendees by relying on e-mail marketing campaigns. This was before the opt-in and spam crackdowns, but I had small e-mail lists and, often, small classes. When I began to use direct mail postcards, a phone blast system and the old stand-by, fax blasts, I got much better numbers. Some older property managers are still not too thrilled about the Internet. They don't open e-mails from people they don't know, they aren't hanging out on portals like Multifamily Insiders. We don't want to just ignore them, so we market the ways that reach them.