Actor Brenock O'Connor (best known for Game of Thrones) talks a little in this interview about Dickensian, in which he'll be playing Peter Cratchit. Speaking of which, I've been updating the cast list for the show as information has been trickling in; go here for the latest information!
Roger Rees, the actor who won an Olivier Award and a Tony Award in the title role of the 1980 Nicholas Nickleby adaptation (and later earned an Emmy nomination for the U.S. televised version), died Friday at age 71. Rees also played Fred, as well as acting as narrator, in the 1984 television adaptation of A Christmas Carol.
According to this page, Mike Newell is set to direct the upcoming miniseries version of A Tale of Two Cities. (Newell, you may recall, directed the 2012 feature film adaptation of Great Expectations with Jeremy Irvine and Helena Bonham Carter.) There's been no official announcement, but the page belongs to the agent of Alan Bleasdale, the screenwriter for the project, so I'm guessing it's probably accurate.
There've been no official Dickensian casting announcements yet, but word about casting is starting to leak out via actors' Twitter accounts. So I don't think anyone will object if I mention that Caroline Quentin is playing Mrs. Bumble, and Sophie Simnett is playing someone's niece. (Whose niece, I don't know. She looks a bit young for Scrooge's niece.) Additionally, this site lists Stephen Rae as a cast member, though with no role given.
It isn't much, but it's a start -- and I'll let you know if I find more!