Creating specific forums for critiques of whatever (appliances, recipes, shows, etc.) I think is an open invitation for two things, trouble and increased need for moderation.
Regarding trouble, you've created a place for people to complain (yeah, critique, but you know some would complain) about whatever. You've also created a place that could create personal animocity (sp?) because So and So gave a bad review/critique of a product Somebody Else owns and loves to use. Somebody Else then responds to So and So which could quickly lead to negative public communication. Granted we should all be maature enough not to do this, but the best step to avoid it is to not provide the opportunity.
As for the need for moderation increasing for said forum suggestion, the latter part of the previous paragraph demonstrates where the need would come. I know that the forum software has been programmed for foul language editing, but there are ways around that without actually spelling the foul word.
Spawning from GB's post, such topics could be discussed in the current forums. Doing so would still run some risk of animocity within the topic, but being part of a larger, more general forum not specifically described as being for critiques would not draw those just looking to badmouth something or someone. The integrity of the forum remains stronger. The fewer "invites" of sensitive topics the less likely to have to deal with sensitive topics.
This comes from about 6 years of moderation experience at various levels for a few different forums, from psudeo public to completely private. One forum I moderate at still today is running into a similar problem (not a cooking forum), people asking or critiquing things that ought not be asked or critiqued publicly, and arguably in the realm of the forum subject matter.
I concur with GB. Not that I need to or that the staff is concerned that i concur or not, but simply my experience and my two cents.