If you go to this file there are references to all the components you need for the Steam Linux client (as also pointed out in this forum post). They can then be extracted and assembled by-hand by following the same layout as the Mac OS X Steam client. You can then proceed to launch the Linux-native Steam client, but it will have problems connecting to the authentication/update server (but that can be worked around). However, good luck signing into your account as it's setup similarly to the closed Mac beta program where only those accounts of the authorized gamers can partake in the testing process on that platform.
All the Linux client files (read: these are NOT just the server files) are there from the binary to the Linux shared libraries for your exploration. These are the real files for the Steam client Linux release and if you play around with strings you can find other interesting information too.
As the Linux gaming community was horribly shafted once before already by Epic Games with Unreal Tournament 3, that is understandable if you are skeptical until you see Valve's official announcement. However, from seeing these actual files to the other proof and the information from sources, I am 100% confident that the Steam client / Source engine are coming to Linux. If my information is correct, an official announcement regarding this Linux support may be here by this June.