Because before 5.0 I would tap on a name, and bring it up, then decide if I wanted to hit send, or look at my call history with them, just look at their pretty name and number, or something.
NOW when I tap their name, I'm calling them automatically. I've called several people on accident. Most of the time I was just wanting to look to see when the last was I talked to them - and I forget that I have to go someplace else to look at their history, or their phone book entry.
OH MY GOSH!! I've been doing this too. I'm glad to know it's not just me! LOL I really don't like this feature. I also keep calling people when I just want to view contact info...it calls them! WTF is that about? I just want to view their info. So now instead of clicking on their name I have to click BB button and select to view it from there... I figured that out after calling a person 3 times!! YIKES