Maybe you would like to explain what you are talking about? Steam is not going to just go belly up and instantaneously stop play ability for every game ever bought through them.
Steam servers went offline for a while overnight. I noticed an announcement on the Steam forums last night that the servers would be down for service for a few hours starting at 4am Pacific time. I put Steam into offline mode before I went to bed so it wouldn't slow me down from playing some Dead Rising 2 this morning (not that I needed to do that, Steam will allow offline login if it can't connect to the servers). The servers seem to be back up now, ahead of their anticipated schedule. EDIT: Nevermind, that downtime is scheduled for Monday morning, not today.
On topic: I'll be buying retail (hopefully the CE) because:
I like to have the physical manual for a game that I'll be playing a lot of/playing for a long time (not that I need it, just nice to have);
Having the disk allows me to easily reinstall the pre-patch version in the case that a patch messes something up;
I'll still have all the advantages of Steam for the same price, so it's like you get the physical media for free.
For games that I'll play for a few weeks and then forget, I often buy them on Steam.