They should be. It makes perfect sense to have a site about picking the right computing hardware for a task. There's no need to impose a particular format on questions. We do need quality controls — I think we'll end up with guidelines similar to the ones on Software Recommendations — but they apply to teach-me-to-fish questions as much as to feed-me-a-fish questions.
In comparison with Software Recommendations, I think it's even more important to encourage teach-me-to-fish questions, because hardware evolves quicker than software, especially when you take cost requirements into account.
(It would also make sense to have a site that's about computing hardware, including configuring and modding, but that's not the direction we seem to be taking.)
I'm mostly posting this answer in response to Robert Cartaino's.
It's an arguable point, but the problem with these "teach me to fish" questions is that they are on topic at Super User. Generally we do not worry too much about coincidental, overlapping scopes, but the entire premise behind this site is that most communities do not allow specific product recommendations at all.
That's a somewhat precarious premise on which to build a site — i.e. "they don't want these questions elsewhere" — but we are trying to make it work. But what we absolutely cannot allow to happen is to turn this site into an "alternative Super User"… a site where you can ask your hardware questions which also happens to allow product recommendations too. That just cannot happen.
This argument is grossly inaccurate, since the overlap would be small — this site isn't even shaping up to be about hardware in general: only about choosing hardware, not about how to install it, configure it, modify it, etc. In any case sites have been allowed that had even more overlap with existing sites, when they brought something new to the network. There's even a Stack Exchange blog post that explains that communities should stride to avoid
Scope Gerrymandering: attempting to micromanage what’s on-topic in order to avoid overlap with other sites or simply drive away users seen as undesirable.
Robert's argument also inaccurate in that some of the questions that were closed would be off-topic on Super User since they don't fit SU's restrictive definition of “computer” (e.g. smartphones are firmly off-topic there).
The argument for limiting is deeply flawed, yet this is presented as a diktat, allowing no discussion.