Check out this post on peterpixel. It’s about the fact that installer icons enhance the experience of ‘unboxing’ an application. And I must say I totally agree on this, I just switched from PC to Mac (absolutely no regrets yet) and I immediately noticed the difference in installer icons and icons in general. On the mac there seems to be put much more effort in the icon creation process. I think icons should be asking to be clicked. Icons should trigger an recognition/emotion with the user, also icons should reflect the contents of a program.

Go and check out the detail on these icons, and while you are at it download and try some of that software too.

I personally like the Transmission icon.