Guy Ritchie may have surprised the world with his fun, if hardly flawless, rendition of Sherlock Holmes and the box office haul is impressive considering its competition with James Cameron’s Avatar.

I recall the distinct look given across the panel at the London press conference between Joel Silver and Guy Ritchie when the possibility of a sequel was queried. It was a look of quiet confidence and today EW are reporting that the film’s star Robert Downey Jr. has dropped out of Iron Man director Jon Favreau’s adaptation of Cowboys & Aliens due to scheduling conflicts with the fast tracked sequel to Sherlock Holmes.

That Warner Bros are greenlighting the sequel is no great surprise and the chance to see Downey Jr. and Jude Law back on screen bickering and deducing will be welcomed by many people who enjoyed Ritchie’s film.

There is no news yet regarding the rest of the cast (although the loss of Mark Strong’s character to the series will be felt) or who will be directing but given the critical and commercial success of Sherlock 1 the decision to keep a strong team together is elementary. A June shoot is expected with a 2011 release looking likely.