I just finished up both seasons of Torchwood and the mini-series. Here are a random collection of thoughts.
1. The characters are not consistent.
2. Some of the Plot Elements seem to use "It's in the Script" motivations
3. Captain Jack is not as fun as he was on Dr. Who. In fact, he's not fun at all, more depressing.
4. Everyone comes across as amatuerish and idiotic, especially people who are military/government types.
Here be spoilers!
In the final analysis, I can't recommend watching this.