I use QuickTime alot. It's the fast way to trim a single file or save a file in a different format without phaffing about with other apps.
I kinda like the new interface where the borders all disappear when you are watching, but I really hate the fact that the controls and boarders appear *on* the video whenever you use them.
Take a look at the attached image. I just made a really quick screen video using SnapzPro. I stuffed up my start and end, so I just need to trim it....but the prime part of considering where I trim relates to the top and left edge of my clip....but with the new QT, I can't easily see that top area, because the border that has appeared keeps getting in the way.
Look at the second window on the same image. QT 7 and your entire movie is not obscured in any way whilst trimming. It just makes things so much cleaner.
Phil