Reasons to move to DW : They have policies and management strongly supporting privacy, tolerance, and accessibility. They don't have ads. They have made some significant improvements to the LJ codebase which they started with, including separating the "friend" concept into "people you read", and "people who can access your locked posts" (but with more succinct names than that :-) ). And they have tools to make the migration process as painless as possible, including an import tool which can bring in entries, comments, icons, etc from other LJ-based sites.
 For those that didn't notice, the latest round includes Twitter/FB integration which makes it easier for people to unintentionally (or deliberately) link LJ and RL identities, and expose comments from locked posts, and generally make a mess of privacy. Apparently they also made mistakes in the reintroduction of Pingbacks (again to do with locked posts), and it looks like a couple of staff members have been trolling in news posts