According to Gavin Barker Associates, John Barrowman (who plays Jack Harkness for BBC's "Torchwood") has confirmed that he will only take part in the filming of the U.S. version of "Torchwood" during January through June of 2011. For, he's suppose to return to the U.K. after June of 2011 for the filming of the season 4 episodes of the hit BBC series itself during 3.5 months.

My guess is Jack Harkness will likely to appear in just early episodes of the upcoming U.S. T.V. series with the show as a whole centering around a different protagonist.

Source: The Doctor In The TARDIS

7:26 PM Canada EST