a band uses the same instruments when they play a song even if its a different song.... you can still tell who the band is. for lack of better analogy, its kind of like that with juice vendors also.
Basically, a "house taste" means that a supplier's juices will have some certain common qualities. For example: I've found that KBV juices all tend to have a certain character to them that is unique to KBV. It doesn't matter if I order the candy bar, special k tobacco, momma's angel wings, whatever....they have a certain KBV-ness to them. This works with most any consisitent supplier, I'm just using KBV because it's easy to type.
I suspect this stems from a combination of a supplier's base liquid, nicotine source, flavoring supplier (or extraction method) and juice crafting philosophy. Some suppliers have a house taste that really agrees with me (BWB), others not so much (Bluemist).
Think of it like food: I'll bet you've got a few restaurants you like a lot, and others you've tried but don't really dig. There's just something about the way things come together at places that gives them a distinct signature. Sure, some dishes (juices) will be better than others and some will be just plain bad, but as a whole, you've got the places you like and the places you don't.
Make sense?
@Manfred1816: How's the vapor on the Joogler Juice. They look promising and they sell cartomizers too, nice.