It would split the Valve fanbase, with most of the bitching and fanboy praise coming from this site. Imaging if Valve, probably the biggest dev who makes games almost exclusively for PC (and this site's GOD) not only put more emphasis on consoles... but MADE a console. The results would be catastrophic... and hilarious to watch.
PC Gamers would cry out "VALVE SOLD OUT! VALVE BETRAYED US!", Valve fanboys would cry out "YAY! THE VALVE (NAME) IS THE BEST CONSOLE EVER! FUCK ALL OTHER CONSOLES! VALVE RULES!", and the other console fanboys... well, they'd keep doing what they're doing right now, but spend about a month going "THE VALVE (NAME) IS GAAAAAAY!", then go back to insulting all the other consoles.
OT: Would I get it? Depends. This gen? No. No real reason. Considering the new Nintendo console will probably have issues next gen with the strange controller, and all other things considered, Valve making a console would probably still be better than anything Sony and Microsoft put out there... plus, it'd essentially be Steam, but in console form, meaning it's OnLive, but it DOESN'T suck.