5) Automated patching. Nothing special, but when I tried steam, I was very impressed by its "smart" bandwidth usage. Every time I tried to play a HL movie it was already downloaded, but whenever I'm playing online games/downloading, steam doesn't get in the way (you can monitor its bandwidth usage).
This, to you, is a good thing? It seems to indicate to me that STEAM decides what gets sent to my harddrive instead of ME deciding it.
Don't worry, YOU still decide what you want STEAM to download automatically. Each game can be set to autopatch (or not) and each content section allows you to decide whether it is predl'ed or not. It worked out pretty well. As soon as I saw a new HL2 movie on Blue's I already had it avaliable to run.