The tv series is a complete reinvention of the original TV series. Now I'll admit I can't remember the original show hardly at all (it ran from 1976-78 in the States) but I've been told that the vast majority of the new and old show have no similarities apart from the core concept and the main characters name (Jamie Sommers).
You can also tell that the series have been reinvented by the same team who reinvented Battlestar Galactica for TV a few years ago. There are several actors who crossover (the most notable being Katee Sackhoff who plays Starbuck in BSG and Sarah Corvis (the original Bionic Woman the military creates) in this series. Mark Sheppard (who plays Anthony Anthros - one of the founders of the project) also appeared in several episodes of BSG but seems like he'll have a much larger role in this series.
My overall impressions of the first episode of the Bionic Woman have been favourable. It hasn't hit me as *wow* as some series but then it's rare for me to go *wow* based upon a single launch episode (Deadwood was a *wow* moment; Firefly wasn't but soon become so after a couple of episodes). I'll certainly keep up with the series for a bit to see how it develops. It certainly got a very big viewship in the States (13.9 million - making it NBC's biggest midweek premier since The West Wing in 1999) so the show has some hope of survival!
US Success As Bionic Woman Debuts (BBC News Online; Friday 28th September 2007)