You can tell who the target audience is

Rating: 5/10 (30 October 2007)

and I'm not one of them.
Transformers had impressive special effects. But the acting ws subpar and plot was written for a younger audience. Megan Fox's sweet bod was, in my opinion, the best part of the film (narrowly beating out the special effects) My roommate rented the video, so i paid exactly the right amount for it (nothing). Perhaps on the big screen the special effects would have been more captivating but i found myself glancing at the clock on the wall wondering how long the film was. I discovered it was 143 minutes long and I felt it was probably about 43 minutes too long. I can't believe that the entire story couldn't have been condensed at some points.
Overall Transformers was an average film that had decent special effects to keep it from being a stinker. I give the Special Effects an 8 and the film as a whole a 4. Not good, not hideous and possibly better than anything i could have watched on TV tonight.
Edit-After reviewing other comments, I realized that for many Transformers were part of childhood/growing up. I also remembered that in the 80's I was in high school and i was far more concerned with how to get into Tracy L's (I'll refrain from using her last name) pants than anything concerning toy robots. So I when into this film unbiased by childhood memories. ((Unlike when I watched the re-release of episode 4 (known as STAR WARS when I saw it back in 77-78)The trouble was that the kid that saw Star Wars was grown and the magic was lost in the tide of life)) Anyway, apparently lack lack of bias didn't help much, the film simply wasn't very good. At least I didn't feel part of my childhood memories were being violently tread upon (like others have implied). I also learned that a lot of the charm of the Transformers, the development of their personalities was apparently too (tedious? frivilous? unnecessary? expensive? useful? ) to be added to the movie. Shame.