I've been getting interested in virtual book tours as a promotional tool. More and more authors are doing them nowadays and I'll be hosting my first this June both here and on Grizzled Old Traveler. Science fiction author and fellow Canadian Christopher Hoare has an interesting summary of his experiences with a virtual book tour on his blog.
In a nutshell, it helped him network with other writers, but it didn't generate a huge response. He seems upset about the lack of comments on the posts, something I've been having trouble with on my blog (say something, people!) but since he hasn't seen this quarter's royalty statements yet, he can't say how it's affected sales. As Chris points out, it's only one tool in the promotional tool box.
His Iskander series and two anthologies he has contributed to are available from Double Dragon.