I still don't understand what's wrong with steam, it has a lot of nice functions like achievements, downloading rate of 4-6 MB, file verification if your install is corrupted, they just added a function where you could decide which disk you can install the games on, all your friends are on steam as well. You can even run all of the paradox games with steam offline. Hell im with steam since I bought half-life 2 in 2004. I've never had any problem with it whatsoever.
But what most appeals me is the ability and the platform they provide to download and install the game very easily. Yes others site have that ability aswell, but for me steam provides a better platform than the others do, by far.