Recently I hooked up my computer to the TV specifically to use it as a powerful console (at the time, primarily for Sleeping Dogs and Transformers Fall of Cybertron). Rather wish this was actually live already as it'd be spot on.
Looking forward to it.
More promising is the potential for specific Steam hardware designed for this. This is exciting for a couple of reasons:
1) An open, customisable 'console' running a full range of PC games at potentially full power (or at least above the curve capable of contemporary consoles) is pretty enticing. Especially if the entry cost and technical ability is lower than setting up your own gaming PC.
2) The most likely platform for such a piece of kit would be Linux (running Windows would require a costly licensing agreement with Microsoft and Valve to change their mind about how much of a 'disaster for gaming' they feel Windows 8 will be [though I disagree]). This is a very good thing because a Linux Steam client may open up the opportunity for some good support - but most developers won't see the benefit to the Linux PC market to make it worth the cost. However, a more simple console-like piece of hardware would be a lot easier to sell to publishers/developers and support for the platform itself will grow in turn.
In fact, one could probably say that a Linux Steam client is practically dependent on such a piece of hardware going on sale, and likely vice versa.
Anyways, I'm looking forward to seeing what Valve have coming down the line. None of it, I expect, will have the number three in it, but as far as Steam stuff like this goes - I'm very happy to lap it up.