The value of the deal is causing intense speculation. It is believed that Sci-Fi channel turned down the original 2005 offer, and the current one is therefore cut price! The BBC has obligingly put the US box set release back to July 4th.
What is likely to make a difference in terms of ongoing production are the other overseas sales (it has sold into 17 markets, more than it's ever had at one time before) and the domestic ratings. Significantly while Who is co-produced by the Canadian Broadcasting Corporation, Torchwood is all in house (BBC Wales and BBC Three).
All of which speaks volumes about the last 15 years. The rights for a movie were actually on the market during the McCoy era. The effort it took to make the 1996 telemovie was immense, and the fact that it was never repeated killed Who stone dead for another nine years. I'm pretty much on my own that I didn't mind it, obviously wasn't commercial enough. Stylistically the new series seems to be its child. All along all Who needed was a bit of content, a bit of promotion, and a bit of an opportunity.