It always felt to me like the new series of Doctor Who were trying just that little bit too hard to be something they weren't. Holding onto some old traditions like the ubiquitous Sonic Screwdriver while abandoning others such as the design of the Tardis control room made it seem slightly schizophrenic. Torchwood is free to be its own thing without forty years of prior tradition, and it takes full advantage of that.
John Barrowman as Captain Jack Harkness is just as cool as he was in Doctor Who, Eve Myles as Gwen Cooper is simultaneously intelligent, driven, vulnerable and gorgeous (I love that "giant eyes" thing she does when she's surprised), Gareth David-Lloyd as Ianto Jones is intriguing (I'd be surprised if he doesn't end up with a bigger role in later episodes), and Burn Gorman as Owen Harper is just as bizarre as he was in Bleak House. Naoko Mori as Toshiko Sato (who formerly had a cameo in Doctor Who) seems a bit underutilised at this point - come on Russell, give her a few alien corpses to dissect!
I'm finding it impossible to avoid comparing Torchwood to that other new BBC series, Robin Hood. I was expecting Torchwood to suck, frankly, and have been pleasantly surprised by how good it is. Robin Hood on the other hand seems to have missed the target. The actors are all smug, irritating, and far too pretty for their own good. Keith Allen provides some comic relief as a caricature of The Evil Sheriff of Nottingham, but it's not enough to hold the series together, and the issues explored in the stories (the effects on the English peasant class of being taxed into the ground to fund a religious war in the Middle East) are so oversimplified that you have to be careful not to think or it all unravels. As a result I'm having a hard time suspending disbelief long enough to enjoy the series for what it is - light entertainment with archery and silly costumes.