Had an elaborate post prepared, but rereading it was boring, so lets keep it simple, cause this is a simple topic.
According to the TTB's Standard's of Identity; 27 CFR, Part 5, Section 22 (google 27 CFR 5.22), the definition of vodka is provided as part of "Class 1: Neutral Spirits or Alcohol", and comprises the following:
Therefore, to the artisans out there who make vodka too. What do you call vodka? Is some character permissible, or "no way Jose"?
Personally, I'm in the "no way, Jose" camp. Any distillate with noticeable odor and/or flavor should not be permitted (by the TTB) to put "vodka" on their label.
Q: What's noticeable?
A: If you make a martini with it, and before it's to your mouth you are thinking "What in the hell is that odor?", that would be noticeable to me, and I can name 5 brands quickly that fit into that category...
Q: What would it be called then?
A: I dunno, brandy? Schnapps? Anything but vodka...
Q: How does one enforce such a rule?
A: Don't know either...I guess with their (the consumer's) wallets.... ?
Anyway, what do you think?