are threads asking for suggestions support or not?
Depends on suggestions for what. Even if it's a question about say mp3 players, I would consider that support because it's helping the poster make some sort of purchase. I don't think that sort of stuff should be allowed in /g/ because it doesn't really add anything. An exception would be talk of a new mp3 player using some new tech or design methodology and comparing it to current standards. However, suggestion threads are fairly innoculous, so it's more on a case by case thing, but I would personally consider them support.
Well, I think it was said before, but it may not be the accepted that support threads are like "Spyware, what I do?" "Adaware logs" "ENOUGH IS ENOUGH, I WANT THESE MOTHERFUCKING VIRUSES OFF THIS MOTHERFUCKING COMPUTER" "My computer won't see my new printer". Mostly threads talking about products will talk about what's good and bad, and that itself is support, but not the type that is trying to be stopped from being posted.