The highlights:
Green-lit for a fourth series… to air in Summer 2011 (only a year to go!)
Jack and Gwen return… with new cast
10 Episodes for the fourth installment
Picked up by Starz here in the US, whose funding, evidentially, has been what has put it on track to get made.
More Info:
http://ausiellofiles.ew.com/2010/06/07/starz-acquires-torchwood/
http://www.guardian.co.uk/media/2010/jun/07/torchwood-return-fourth-series
http://www.variety.com/article/VR1118020302?categoryId=14&cs=1