The reason why most big screen movies based on TV shows fail is because the filmmakers fail to understand that it's not the concept or plot that is so good about an old TV show that will translate well to the movie theater, it's the fact that the TV show was a product of it's time. It had a certain "feel" and cast that were special not only to their time but to what we, as viewers, were experiencing as well. For example, was Charlie's Angels such an incredible idea for a show that it just screamed for a big screen treatment? No. It was the '70s and Aaron Spelling and the whole Farrah phenomenon that made it what it was. That's why the two Charlie's Angels movies were so horrendous. (Well, OK, among many reasons.) Very few movies based on TV shows get it right. The X-Files worked because it was bascially a bigger budgeted ep of the show, with the same cast. Mission: Impossible borrowed the name only, really, and worked on it's own.  Most of them (The Beverly Hillbillies, The Fugitive, Lost In Space, etc) just sputter and die.  

That's why the trailer for Bewitched is so surprising. It not only looks good, it looks very funny and actually worth seeing. Nicole Kidman has the Elizabeth Montgomery look and nose twitch down pat, Will Ferrell looks like he's in top form, and it looks like they're going for an inventive Brady Bunch Movie vibe that just might take it from lame idea to inspired. This could be fun.