You're not alone. It's an on-line multiplayer FPS with a huge following. Anyways... if you do play, you will prolly be seeing this Steam Is Down
page alot. It is supposed to be a tool that will auto-patch your games (seamlessly without you knowing) so you are always up-to-date. But it is causing major headaches for gamers (including myself) who can't play a game that two weeks ago worked fine.
Normally with CS you have two components. You, the gamer, with your game (the client). And the game server, which there are tens of thousands of, all running on their own, independently, with no affiliation to Valve (the company that makes CS). With Steam, Valve has thrown an extra piece into the mix (I say this piece is a wrench). The client no longer connects to the server. First the client must connect to steam, then it can connect to the server. So if Steam is down, you can't play the game. Not even a LAN game. But its even more complex than that. Previously, you would open the game, be able to change your options, go into a practive mode, and then when you wanted to actually play a game, go to the Net Games screen, and if you had problems with your internet connection, you would get no server info and not be able to connect. All the while, you know what's going on.
Steam has this horrible interface. You dbl-click on the Steam icon... and no window opens on your screen... you are left wondering if you really dbl-clicked or not. Then after a pause the window will finally open, or, with the server problems, you will get a window telling you to check your connection or try again. You click the OK to close this window. And if you try to open Steam again too fast you get an annoying window saying that Steam is already running and you can't have two copies open. This is a weird experience for a user, cos there is no icon in my system tray, and no window open.
There is a solution for Steam. Don't have people hit your server as they open their client, have clients check for updates on a weekly basis, or check for updates when a game server tells a client that they are not up to date.
Note: This is incomplete. I just wanted to post it while fresh in my mind, I will come back later and add some edits and URLs.