As an avid reader who has been using Goodreads for years, my reason for not switching to an alternative has almost nothing to do with any of what the author mentions. That reason is purely the promise of stability provided by a site that's been around for longer (not to mention the big-name ownership) - the faith that Goodreads will stay running for years and years into the future.

When it comes to the list of books I've read, I want to set it and forget it - and with a small upstart, there's always the worry that the maintainer will run out of money (or interest) and shut the service down. Sure, most of these book sites have import/export functionality, but why bother with that when Goodreads will likely be around for a long time?