No. Launch hype doesn't correspond to long-lasting sales. If Valve can get their Steam Machines on the market just after the initial hype of a new console gen fades, then they can be somewhat successful. I'd never believe Steam Machines to sell anywhere near a gaming console, though.

The steambox is going to bomb LOL.

I have also come upon this, while searching for info

http://www.dailyfinance.com/2013/11/16/is-valves-steam-machine-a-viable-competitor-to-pla/

Seems, it has bothered some people already.

I believe they are an alternative to a new PC. But I don't think they will be successful or noteworthy, because they don't solve the issues of gaming PCs (too many choices and tech spec nonsense), they remain DRM'd (no other programs allowed), and they don't have any exclusive content to drive sales.

They are definitely not a console though.

Are Steam Machines even competing with the PS4 and X1? I figured they were just gaming PCs with Steam OS

I think the steam fanbase is way overestimated. People are fanboys of PC gaming (myself included). I happen to also game on consoles but most PC gamers have absolutely ZERO interest in consoles and it doesn't matter how much they like steam on a PC they won't even consider a console version just because steam made it. The steambox is a concept desperately searching for an audience, it is either going to have to compete directly against the Xbox and PS or it is going to have to somehow convince the legions of PC gamers that they really should be console gamers (good luck on that one).

Hard to say, on one hand one could say that the PS4 and One will steal the momentum and attention but, on the other hand, there's a case to be made by stating that the demographics for the Steambox and the PS4/One likely aren't the same.
The Steambox appears to be aiming more towards a "living room PC" kind of crowd and would probably focus on different games as well.

I'm a lot more excited about SteamOS though, that could really become something over the next five years or so.

People expecting SteamMachines to compete with the big 3 consoles are going to be sorely disappointed. This is not going to be moving millions of units.

Exactly, it was never meant to compete with the other home consoles. I do think that one could sneak its way into at least two homes though; yours and mine!

It's about time someone that is not Nintendo brings something new to the good old and boring console scheme.

Even if the machine itself flops, Steam is a PC environment and I'm sure anyone running steam on whatever OS na still play with the steam controller, so this thing is already a success even before launch.